Documenting Lessons Learned

Each new project provides a unique opportunity to learn something new and then apply it to improve the planning and execution of future projects. The body of the knowledge gained while working on a project is sometimes referred to as "lessons learned."

Some of the most common lessons learned from the schedule control process are:

• the causes of variance
• the reasons a particular corrective action was chosen
• the new processes that were implemented
• the issues with internal or external sources
• the successes or failures measured

Because lessons learned are helpful in planning future projects, care should be taken to document these lessons and make them available to future project teams. Consider the following example.

A company's planned launch of the space shuttle was set for April 1st. During the pre-launch servicing stage, workers inspected and tested the Orbiter wiring. During the testing a system malfunction occurred. Upon examination, the team discovered a short circuit in the wiring, which caused the malfunction. A complete system rewiring would be required. This procedure could significantly delay the project, since the wiring would have to be ordered from a specialty supplier in Europe.

The project team and shuttle crew met to discuss this dilemma. The team decided to increase the number of project workers. This would allow the rewiring to be completed while continuing with the remaining pre-launch servicing and testing. The target launch date could still be met.

The need for complete system rewiring and ordering the wires from an outside supplier was what caused the project to fall behind schedule. Therefore, the detection of the cause for the schedule variance was one of the lessons learned by the shuttle team.

Another lesson that can be recorded in the historical database is the approved corrective action. Adding more resources was positive and ensured the successful completion of the project. The target date was achieved.

A toy manufacturing company has just designed and developed a prototype of a new infant toy. The toy is to be launched at the International Toy Fair in two months. In order to prepare, the company needs to produce 2,000 prototypes, which will be available for sale at the fair. The project is running on schedule. However, during the testing phase, the company discovers a flaw that could cause the toys to malfunction. With only three weeks to go, the company cannot possibly start from scratch and reassemble 2000 toys.

Closer examination reveals that fixing the problem simply involves ordering a different part and replacing it. This will take at least one month, working solely with the current team. Management's only option at this time is to add project personnel, allowing the project to be finished in time for the toy fair.

A lesson learned, in this situation, is the discovery of the variance from plan. The manufacturing flaw resulted in the need to order and replace a fundamental part of the toy. This unanticipated problem has the potential to significantly delay the project's completion.

Another lesson learned is the reason for the corrective action chosen. Increasing man-hours by adding project personnel is the only viable option for the toy manufacturer, given the time crunch.

Once a project team has identified the lessons learned through the schedule control process, there are a number of succeeding steps that should be implemented to ensure the information is not lost.

• Step 1: Record lessons learned - Information should be recorded and stored in a way that permits team members to easily identify any applicable lessons learned. This information is invaluable when planning projects and processes.
  
  
• Step 2: Analyze information - Lessons learned should be analyzed to assess improvements, or identify valuable or detrimental project trends. The analysis should focus on improvement efforts.
  
  
• Step 3: Measure effectiveness - Lessons learned programs should include a means for measuring project effectiveness. The purpose of measuring effectiveness is to determine if information is being disseminated and past lessons are being incorporated.
  
  
• Step 4: Review and validate information - Lessons learned should be reviewed and validated for appropriate personnel to determine accuracy and applicability.
  
  
• Step 5: Disseminate information - Information about lessons learned should be disseminated to all project team members as well as key stakeholders. Information dissemination may be accomplished through a variety of vehicles, the most common being written documentation or through meetings or workshops.
  
  
• Step 6: Archive irrelevant information - Information that no longer has relevance to organizational activities should be archived or eliminated. Archiving is often the preferred choice, as currently irrelevant data may have inherent value in future project planning.
  
  
• Step 7: Obtain feedback from stakeholders - Feedback from key stakeholders and users can assist saving time or money, preventing a recurrence of a problem, or improving project design or processes.

To ensure project quality, you will want to use the new insights and processes that result from lessons learned. To benefit from this practice, lessons learned must be well documented and reviewed occasionally to determine if past lessons are being realized and integrated into project planning and ongoing development.

Taking Corrective Action on Variances

Corrective action is a crucial output from schedule control. It involves implementing a pre-determined plan of action to bring expected future schedule performance in line with the schedule baseline.

Once a significant variance from the plan occurs, the next step is to determine whether corrective action is needed. At this stage, the project team should ask:

• Has the schedule baseline changed?
• Have milestones or critical activities been missed?
• Will implementing corrective action expose risks?

Once you have determined that corrective action is required, there are a number of possible actions to take.

• Renegotiate project requirements - When achieving the desired outcome appears to be impossible, you can talk to the client about renegotiating the project requirements.
• Reallocate resources - Another option is to reallocate resources from a future activity. This allows for recovery of the current problem and provides time to repair future problems before they arise.
• Narrow the project's scope. - Certain variances are best addressed by narrowing the project's scope. In this case, you need to determine which activities can be compromised without jeopardizing the project, then cut back on those activities, or eliminate them if possible.
• Add resources. - Other variances may call for additional resources. Here, your goal is to look for opportunities to add resources that will positively affect the critical path and help bring the project back on track.
• Subcontract work out - Another possibility is to subcontract work out to companies that can perform the activities at a lower cost. Subcontracting allows the project team to concentrate its efforts on other, more critical, areas.
• Partial delivery - Another option is to talk with the customer about the possibility of making partial delivery. This may be the only way to satisfy the customer's critical requirement and keep the customer happy.

When a problem arises, you need to determine its cause. You must then review your schedule management plan and determine whether corrective action is necessary. If so, you need to meet with the project team and key stakeholders to determine the best option and follow up with the client. In this way, you can arrive at viable, workable options that are acceptable to all.

Updating the Project Schedule

To accurately reflect your project's progress, project schedules must be continuously updated. This process enables stakeholders to evaluate impacts to the project as they occur. This provides better control over the project and reduces the impact of required changes.

A schedule update is any modification to the schedule information used to manage the project. Schedule updates are required when variances from plan are higher or lower than the previously approved limit. Schedule updates may or may not require adjustments to other aspects of the overall project management plan.

There is a special category of schedule updates called revisions. Revisions are changes to the scheduled start and finish dates in the approved project schedule. Typically, start and finish dates are only revised in response to scope changes. In cases where schedule slippage is severe enough to warrant revision, rebaselining may be required to provide realistic data for performance measurement.

Palmcom Computers is developing a new palm-sized computer. The company has planned for the product to be introduced at the Fall Buyer's Show. It has decided to strive for this date, to get the heads-up on the competition. Reaching this goal allows for very little flexibility. At the end of the second phase, the management team notices that the schedule is slipping, resulting in a variance much larger than the acceptable range. If this trend continues, the company will not have the originally planned two weeks for quality testing.

In this example, the company has two choices—alter the project scope, or change the project schedule. After careful examination, the team has decided to maintain the current completion date and adjust the allotted testing time to one week to give the team an extra week for production.

Ongoing monitoring and updating are essential components of project schedule control. Adjustments to the project start or finish date (revisions) require special attention. In the event a revision is necessary, the schedules need to be accurately revised for the key stakeholders to continue to have a valid means of measuring the project's overall progress.

Analyzing Schedule and Cost Variances

Have you ever had difficulty meeting a project deadline? Variance analysis can be used during the schedule-monitoring process to compare target dates with actual start and finish dates, thereby detecting any deviations from the plan and allowing you to implement corrective solutions.

Variance analysis is widely used to measure the performance of a project's cost, schedule, resources, quality, scope, and risk. A variance in any of these areas is the difference between what is planned and what actually happens.

Variance analysis in project scheduling is most often used to measure deviations in cost and schedule from the planned budget.

Cost variance analyzes any deviations from the planned dollar budget. Schedule variance analyzes any deviations from the planned completion dates of an activity. Cost and schedule variances are both calculated based on costs and are represented as a function of cost.

When applying variance analysis, figures are obtained from the performance measurement information in project plans and work results. The three key areas for calculating variance are: earned value (EV), actual cost (AC), and planned value (PV).

Earned value (EV) is all the budgeted costs for an activity completed during a period of time. It includes any overhead costs.

Cost variance (CV) examines an activity by comparing the difference between its estimated cost and the actual cost.

Planned value (PV) is all the approved, estimated costs for the work scheduled to be completed for an activity during a period of time.

If the cost variance shows a negative value, the activity costs more than what was estimated. If the schedule variance shows a negative value, the activity is behind the estimated schedule. Depending upon the threshold or contingency, the negative values may be a cause for concern and must be reported. If contingencies were created in the budget to handle cost overruns, then a negative value in scheduling or in costs may not be a cause for concern.

When monitoring a project schedule, you can use variance analysis to identify any deviations from the plan and to ensure that your project does not fall behind schedule.

Considerations When Buying Project Management Software

There are a wide variety of project management software packages available for your company to choose from. All the packages have the capacity to produce eye-catching charts and graphs. Software packages, that will run on your PC or network, are available in varying levels of complexity and at prices ranging from $25.00 to $10,000.00 or more.

Project management software packages can perform many tasks that, in the past, have proven to be very labor-intensive. Depending on the package your company chooses, the capabilities can be limitless.

The introduction of project management software packages helps companies reduce the amount of time and money spent on project monitoring and control. Since the software provides information more quickly, less personnel hours are required for these tasks. Therefore, personnel can concentrate efforts in more constructive, beneficial areas.

There are a number of other benefits to using software, including:

• the ability to track planned versus actual dates
• the ability to forecast effects of schedule changes
• the ability to calculate mathematical analysis and resource leveling
• the ability to examine schedule alternatives early
• the ability to design, simulate and enhance schedule control processes
• the ability to monitor multiple projects simultaneously

Project management software ranges in price from $25.00 to more than $10,000, so you will want to know what type of user you are before you go shopping. The most basic questions to raise before you shop for project management software are:

• How many projects is your company managing at one time?
• How much time and money does your company have to invest in a software package?

High-end users manage multi-projects, and schedule and track many people simultaneously. Packages range in price from $2,000.00 to $10,000.00 or more and require a lot of time to master the features.

Mid-range users may have two project running at once. Projects can have up to 2000 tasks. The cost can range from $200.00 to $500.00 for packages that offer a range of planning, scheduling and tracking tools.

Low-end users can automate the basics for under $100.00. The basics would include tasks like developing plans, occasionally preparing status reports, and producing simple Gantt and PERT charts.

In addition to knowing what kind of user you are, you also need to know how you will plan and manage your projects. Is your company one that emphasizes work or durations? Having this information on hand will affect how easy a software package is for you to use.

Consider resource-driven scheduling when you want to plan and track using detailed work estimates. For instance, if a project will take 592 person-hours to complete, you will need to purchase software that provides scheduling based on work.

Consider schedule duration if you want to focus on the duration of the project. For example, if the project will take an employee 2.5 months to complete, you will need to ensure that your software provides efficient handling of durations.

A key point to keep in mind is that your company's needs will dictate the software you choose. To ensure your time and money is spent wisely, decide on your user type and management style prior to making this investment.

Methods for Evaluating Project Performance

Author Thomas S. Monson said: "When performance is measured, performance improves. When performance is measured and reported back, the rate of improvement accelerates."

In the area of project management, performance measurement techniques are used to assess the magnitude of deviations from the original project plan. As such, they are an important aspect of project schedule control, allowing the project team to determine whether a schedule variance requires corrective action.

There are four basic performance measurement techniques: performance reviews, trend analysis, earned value analysis, and information distribution.

1. Performance reviews
   Performance reviews are meetings held to assess project status. Most project managers schedule weekly, bi-weekly, or monthly reviews to keep the management team abreast of the project's status. By conducting frequent performance reviews, variances are more readily detected and can be addressed sooner which prevents further deviation from the plan.
   
   
2. Trend analysis
   Trend analysis involves examining project results over several reporting periods to determine if performance is improving or deteriorating. By plotting report results on a graph, management can determine whether schedule performance is progressing or regressing.
   
   Companies use trend analysis for long-term projects, to compare status over several periods. Either a three-month, four-month, or six-month moving average is used to predict project trends. Trending provides management with advance warning of adverse trends, and allows for corrective action to be taken to rectify the situation. Companies also use trend analysis data to plan future projects that are similar in nature.
   
   
3. Earned value analysis
   Earned value analysis is the most commonly used method of performance measurement. It integrates scope, cost, and schedule measures to assist the management team in assessing project performance.
   
   Earned value analysis compares the amount of planned work to what was actually accomplished. This involves calculating three key values for each activity that is performed.
   

- The planned value in a project is the approved estimate of cost planned to be spent on an activity during a given time period. - The actual cost in a project is the total costs involved in completing the work for an activity in a given time period. - The earned value for a project is the value of the work actually completed during a period of time. These calculations allow project managers to see whether cost and schedule performance is proceeding as planned.

4. Information distribution tools and techniques
   Information distribution tools and techniques make necessary information available to project stakeholders in a timely manner.
   
   Information regarding a project's performance is essential to bring about project success. Too little or incorrect information could lead to misunderstandings and changes that are not really necessary.
   
   Clear communication and shared information retrieval and distribution methods are the basic tools and techniques for ensuring that important information is distributed.
   
   Communication skills are used to exchange information. Whether communication is written, oral, internal, external, formal, informal, vertical, or horizontal—the sender must ensure that the information is clear and complete while the receiver confirms that it is properly understood.
   
   Information retrieval systems allow information to be shared by project team members and stakeholders. Such systems may include project management software, electronic databases, and manual filing systems.
   
   Information distribution methods ensure that important project information is distributed to the stakeholders. Project meetings, voice mail, electronic mail, fax, videoconferencing, project intranet, hard-copy documentation, and shared databases are all effective distribution methods.
   

Performance reviews, trend analysis, earned value analysis, and information distribution tools and techniques are important in assessing the magnitude of any project variations. Using these techniques to determine whether a project is performing as planned will help you maintain a concise and controlled project schedule.

What is a Schedule Change Control System?

Changes to the baseline schedule represent significant changes and require more than a simple "yes" or "no" approval process. A schedule change control system is a collection of formal, documented procedures defining the steps involved when contemplating a schedule baseline change.

A schedule change control system:

• defines schedule change procedures
• is a decision-making guide for the project management team
• enables your company to assess project changes
• helps your company track project changes.

Schedule change control systems are facilitated by a change control board (CCB) that is responsible for the approval or rejection of change requests. Senior management takes on this decision-making role, in the absence of a CCB.

The schedule change control system itself is a 5-step process.

Step 1: Initiate the change request. - The change request may be initiated either internally or externally. It may take the form of a written or oral request. The change request may be legally mandated or discretionary.

Step 2: Record specifics of project changes. - The recording phase requires the specifics of the change request to be recorded, preferably in a change request log where they can be easily managed. Enough detail must be recorded so that anyone related to the project can understand it.

Step 3: Conduct an assessment. - At the assessment stage, someone is identified as the change request "owner," and must conduct an assessment. Assessment consists of estimating the work involved in implementing the change and quantifying the impact on the remainder of the project as well as on the project's objectives.

Step 4: Recommend a course of action. - A recommendation to accept, reject or modify the change request, is based on the information provided via the assessment. Recommendations should be based on an objective time/cost/benefit analysis.

Step 5: Make a decision. - Recommendations are presented to management for decisions. If the change request is rejected, it is closed and documentation is filed. If accepted, the project budget, schedule, and scope must be adjusted to incorporate the approved change.

Each time a new change request is received, this system is activated.
In addition to this 5-step procedure, the schedule change control system must also include a procedure for making emergency changes automatically. When emergency situations arise, changes may need to be approved without prior review. However, automatically approved changes must be monitored and recorded so they do not cause problems later in the project.

Adhering to the schedule change control procedures will help you decide whether or not a schedule baseline adjustment is required. These sets will also ensure that all change requests are properly managed.

To decide whether or not to make changes to the schedule baseline, project managers must understand the impact the proposed change will have on the entire project. A schedule change control system provides a mechanism for evaluating the need and impact of the change. The system also ensures that a recommendation to accept, reject, or modify the change request is based on objective time/cost/benefit analysis.

Managing Schedule Changes

A schedule management plan is an outline of how schedule changes will be managed. The schedule management plan can be either formal or informal, depending on the nature of the organization. The level of detail the project stakeholders require will determine whether the plan is detailed or broadly-based.

A schedule management plan is an important input to schedule control and can be used as a guide for your entire project. Project managers use a schedule management plan:

• to summarize how schedule changes will be managed
• to direct the management team on change processes
• to ensure that WBS responsibility assignments are controlled
• to make schedule changes traceable

The schedule management plan is just one of the components of the overall project management plan. Other management components include: scope, cost, risk, quality, and communications plans. To adequately assess the schedule impact of actual or proposed changes in all areas of the project, you will want to integrate the schedule management plan with the risk, quality, scope, and cost management plans.

One of the primary reasons for using schedule management plans is to determine how to manage schedule variances. During the project's planning stage, companies determine the acceptable range of variance from the schedule plan. The allowable deviation may be dependent on factors such as a project's life-cycle and accuracy of the original estimate.

For true variances to be realized, input from the risk, scope, quality, and cost control processes are essential. Once the information is incorporated into the plan, it is important to continually track "actual" against "planned" progress.

When it comes to decisions about how variances should be managed, there are four basic options to choose from:

• Dismissal - Dismissing the variance is appropriate when the variance is within the allowable range as stated in the schedule management plan. In this case, no corrective action is required, so the variance can be dismissed.
• Functional modification - Functional modification is called for when the variance is small and within the allowable range, but has the potential to become more problematic in the future.
• Replanning - Replanning is required if the variance is large enough to fall outside the allowable range. Replanning involves reviewing project requirements and redefining project goals. In replanning, less critical activities may be sacrificed to meet time and budget constraints.
• Redesign product - Redesigning the product is required if the variance is way out of range. This is the worst case scenario. In this case, the product description will need to be reconfigured which may result in lower grade performance.

As an input to project schedule control, a schedule management plan is an important component of project management. A schedule management plan helps you manage schedule changes, identify the level of variance, and determine appropriate corrective actions.

Requesting Changes to the Project Schedule

Change requests are another input to schedule control. Change requests are the initial step in making schedule changes. They provide a means for management to review and adjust the schedule and to authenticate and record schedule changes.

Project requirements can change mid-stream. Some of the determinants of change are: competition, customer reaction, technological advancements, and supplier-related conditions.

Changes to project schedules may require extending or accelerating the project schedule. Once the need for change is determined, a company must examine realistic alternatives. Comparing the costs of approving the change with the benefits is essential.

Change request forms are recommended when projects require specific changes. Just as there are reasons for initiating change requests, there are also different forms of change requests to consider—oral or written; direct or indirect; external or internal; legally mandated or optional.

Oral requests - include the rationale for making the changes and the benefits of implementing the changes. Oral requests should be followed by written documentation.
Written requests - describe the suggested change, list affected drawings and documents, and include the reason for the intended change.

• Indirect change requests - can originate at any level of the organization and eventually work their way up the ladder to the project manager.
• Direct change requests - go directly from the team lead or supervisor to the project manager.
• External requests - originate from sources outside the company.
• Internal change requests are made within the company, often within the project team.
• Legally mandated change requests - are the result of new legislation or government mandate.
• Optional change requests - have not been imposed by anyone inside or outside the company.

There are numerous potential reasons for issuing a change request and several different request formats. Understanding the reasons for change and the options for making a request is an important part of managing and controlling project schedules.

Requesting Changes to the Project Schedule

Change requests are another input to schedule control. Change requests are the initial step in making schedule changes. They provide a means for management to review and adjust the schedule and to authenticate and record schedule changes.

Project requirements can change mid-stream. Some of the determinants of change are: competition, customer reaction, technological advancements, and supplier-related conditions.

Changes to project schedules may require extending or accelerating the project schedule. Once the need for change is determined, a company must examine realistic alternatives. Comparing the costs of approving the change with the benefits is essential.

Change request forms are recommended when projects require specific changes. Just as there are reasons for initiating change requests, there are also different forms of change requests to consider—oral or written; direct or indirect; external or internal; legally mandated or optional.

Oral requests - include the rationale for making the changes and the benefits of implementing the changes. Oral requests should be followed by written documentation.
Written requests - describe the suggested change, list affected drawings and documents, and include the reason for the intended change.

• Indirect change requests - can originate at any level of the organization and eventually work their way up the ladder to the project manager.
• Direct change requests - go directly from the team lead or supervisor to the project manager.
• External requests - originate from sources outside the company.
• Internal change requests are made within the company, often within the project team.
• Legally mandated change requests - are the result of new legislation or government mandate.
• Optional change requests - have not been imposed by anyone inside or outside the company.

There are numerous potential reasons for issuing a change request and several different request formats. Understanding the reasons for change and the options for making a request is an important part of managing and controlling project schedules.

Reporting Project Progress and Performance

Project stakeholders often require information about how resources are being used to achieve project objectives. This information is provided through performance reports.

Performance reports summarize project activity progression by comparing your project's performance to its schedule baseline.

Performance reports come in many shapes and sizes. From a time management perspective, the obvious reporting format to use is a graphical representation of project performance. The four most frequently used graphical performance reporting formats are the: Gantt chart, S-curve, histogram, and table.

• Gantt chart - A Gantt chart displays schedule-related data. The dates are shown across the top of the chart to illustrate the time line.
• S-curve - An S-curve displays cumulative costs, labor hours, or other quantities plotted against time.
• Histogram - A histogram is a bar graph of a frequency distribution. The bar width represents the division of each variable into task duration. The height is relative to the number of resources required.
• Table - A table displays semi-processed numerical data for a minimum of two variables. Data is relevant to an individual project's needs.

Each company should determine which format works best for projects, in terms of time and information required. Therefore, the format one company uses may not be an appropriate format for another company.
A reliable reporting system helps to ensure that projects progress according to plan. It can help determine when corrective action is necessary. The reporting system provides:

• regular, accurate status updates
• concise, easily understandable information
• potential problem forecasts.

Performance reports can be presented in various ways, depending on the intended purpose, the content to be included, and the frequency required. Four types of reports that vary in detail and timelines are: current, cumulative, exception, and green-yellow-red reports.

Current reports
Current reports document progress solely on those activities scheduled for work during the reporting period. Reports show activity highlights and any variances from a project's plan. Follow-up on current reports should provide project details, including reasons for variances and a recommended corrective action plan.

Cumulative reports
Cumulative reports examine the project's history—from start-up to the end of the current reporting period. Cumulative reports display trends in project activities that, over several periods may exhibit improvements or chronic problems.

Exception reports
Exception reports are high-level summary reports submitted to senior management. Sometimes these reports are followed by an additional report if more detail is required.

Green-yellow-red reports
Green, yellow, and red reports are very simplified versions of performance reports. These reports get the intended point across with a minimum amount of reading required.

• Green reports - Say that everything is going according to project's plan.
• Yellow reports - reveal a schedule slippage with a corrective action plan.
• Red reports - indicate a project is out of control with no action plan in place.

AC Technology is a computer company that has just reached the half-way point in its newest project. It is designing an operating system that includes its own anti-virus component. Using a cumulative reporting system allows the team to look back and see that the first quarter showed a slight schedule slippage. A corrective action plan was set up to try to offset this problem. Now, the project has reached the end of the second quarter and the reports are showing that this trend has continued. AC Technology must look very seriously at its current corrective action plan and make adjustments to bring this project back on track.
Comparing project performance to the schedule baseline will be easier once your company selects the most appropriate performance reporting format and method of presentation to meet its needs.

Controlling Project Schedules

Another input to project schedule control is the project schedule. Project schedules are a set of planned dates for performing activities and meeting project milestones.

Project schedules are not considered complete until they have been approved. The approved schedule is known as the schedule baseline. A schedule baseline is a fixed project schedule that is the standard by which project performance is measured.

The schedule baseline is only adjusted when the project's scope has been significantly altered as, for example, when the project scope has changed.

When baselining a schedule, you need to consider project activities, dependencies, estimates, constraints, assigned resources, and resource availability.

• Activities - Before baselining a schedule, it must be as complete as possible with regard to identifying all of the project's activities. If you overlook an activity, the schedule may need to be altered in order to add the activity later.
• Dependencies - Network logic must be included in the schedule. Dependencies from other projects should also be considered. If, for example, you plan to start Project C on March 1st, but the resources will not be available until Project B is complete, this dependency must be built into the schedule.
• Estimates - Estimates for activity duration and work effort must be reasonable. If you allot only 60 hours for a 100-hour activity in an attempt to cut costs, you are setting an unreasonable estimate which will affect the effectiveness of your entire schedule.
• Constraints - All known constraints must be accounted for. If an employee needed to complete the project is only available for three months, you must account for this constraint in the schedule and make every effort to utilize this resource within the time he is available.
• Assigned resources - Resources must be assigned to activities in a realistic manner, for example allowing for vacations and down-time. Resource requirements must be reviewed and compared to known capacity.
• Resource availability - The scheduled dates must take resource availability into account, which means the schedule must be leveled manually or automatically. If you know that a supplier can only deliver its resources at the end of phase one, you should not schedule the activity until then.

The schedule can be baselined and used to measure project progress once you have carefully considered these project schedule inputs. Then with a baselined schedule in hand, you can begin the process of deciding which method to use to present the project schedule data.
Tom, the new project manager for Askme Consulting, is beginning his first project: constructing a new office complex in Manhattan. He is reviewing the work breakdown structure developed in the initial planning and estimating stage of the project proposal. Tom and his management team meet to determine the most appropriate method of presenting the schedule for this extensive project. The team needs to determine the types of information required when reporting the project's progress and predicting its future.

The methods they are considering are: the milestone chart, project network diagram (PND), time-scaled network diagram, and Gantt chart. The method they choose will depend on the variables they need to monitor and control as the project progresses.

• A milestone chart is a summary-level schedule identifying the major activities or deliverables of the project. It can become the skeleton for the master schedule. A milestone typically marks the end of an event or the completion of an activity. For example, the first milestone activity for the Askme Consulting project is architecture/design. The second milestone activity is the foundation work.
• A project network diagram (PND) is a schematic display of the project's activities and the logical relationship between them.
• A time-scaled network diagram is a variation of the PND. The positioning and length of the activity represent its duration.
• A Gantt chart is a graphic display of schedule-related information. A typical Gantt chart displays activities, dates, and durations. Gantt charts are the most convenient, commonly used, and easily understandable method of data presentation for project planning, resource scheduling, and status reporting.

Once you are familiar with the various methods of displaying project schedule data, you can use the information for conducting performance analysis. The Critical Path Method (CPM) plays a vital role in this analysis process. Critical Path (CP) is a series of activities that determines the earliest possible completion date for the project.
CP is the longest full path in the project. CP activities have little or no float. As activities are completed, the critical path may be altered. The CP can be determined for the entire project, a milestone activity or a sub-project.

The CPM is used to predict project duration by analyzing which sequence of activities or path has the least amount of scheduling flexibility or float. The early start and finish dates for each activity appear above the node on a Project Network Diagram. The late start and finish dates for each activity are below the node.

Early dates are calculated by means of a forward pass using a specified start date. Late dates are calculated by doing a backward pass, starting from a specified completion date. The most effective way to ascertain the critical path is to perform a forward and then a backward pass through the project.

To perform a forward pass, look at the first activity and determine its earliest possible start date. This is called early start. Continue this process for every activity.

To perform a backward pass, start at the last activity and determine the latest each activity can start without affecting subsequent activity. This is called late start.

Once you have completed the forward and backward passes, you must examine the results. If early and late start dates for an activity are the same, the activity is on the critical path. If there is a difference between the dates, the activity has float time and can be placed on the non-critical path.

Project schedules help you plan dates for performing activities and meeting project milestones. Schedule baselines and critical paths are important aspects of the schedule because they help in project schedule control. Together, these project scheduling tools and methods help project managers to monitor and measure project progress.