The Inputs of Project Activity Sequencing

To successfully plan a project, you have to arrive at an appropriate sequence for the project activities. This process, called "activity sequencing" requires that you identify the inputs of project activity sequencing.

There are a number of inputs that influence project activity sequencing, including: the activity list, product description, mandatory dependencies, discretionary dependencies, external dependencies, and milestones.

• the activity list
  The activity list is a complete list of all project activities. These activities need to be analyzed and organized into a workable sequence so that the project can be completed in an optimal time frame.
  
  If, for example, a computer and data services company is building a network, the deliverables might be decomposed into the following activities:
  
  - configure mail server
  - configure application server
  - configure file server
  - configure print server
  - configure work stations
  - configure the router
  - connect hub
  - run cabling
  - test network
  
  This activity list must now be analyzed for dependencies and organized for completion.
  

• product description
  The second factor that influences activity sequencing is the product description. The product description documents the characteristics of the product or service that the project was undertaken to create. Product characteristics affect activity sequencing. These effects are apparent in the activity list. A review of the product description helps ensure project accuracy.
  
  Consider the example of the computer and data services company that is building a network. Suppose that a review of the product description indicates that the client only requested the configured servers, a configured router, and cabling. The client plans to have in-house technical support connect the hub, run the cabling, and test the network once it is in place.
  
  As a result of reviewing the product description, the computer and data services company supplying the network identifies an inaccuracy in its activity list. A revision of the list and resequencing of activities are necessary.
  

• mandatory dependencies
  The third, fourth, and fifth factors that affect activity sequencing fall under the heading of dependencies. The three types of dependencies that affect activity sequencing are mandatory, discretionary, and external.
  
  A mandatory dependency is one that is inherent in the nature of the work being done. Also known as hard logic, this dependency involves physical limitations.
  
  Take a look at a mandatory dependency in the context of building a computer network. The activities include configuring the network components, running cabling, and testing the network. One mandatory dependency that exists is between the test network activity and the rest of the project activities.
  
  The test network activity can't be done until the network is in place. This means that all other activities must be completed first. There is a mandatory dependency between the test network activity and all other activities associated with this project.
  

• discretionary dependencies
  Also known as preferred, preferential, or soft logic, this dependency is defined by the project management team based on established practices in an application area or a specific desired sequence.
  
  In the example of building a computer network, a discretionary dependency may exist. The client company wants its employees to begin working as soon as possible. To meet with this requirement, the project management team decides that configuring the workstations should be the first activity in the sequence.
  
  Other activities could replace this activity as the first in the project. In this case, however, the project management team decides that configuring the workstations is the preferred starting point.
  

• external dependencies
  An external dependency is one that involves a relationship between project and non-project activities. To understand this type of dependency, consider again, the example of building a network. The computer and data services company purchases some of its network components from a supplier. This creates an external dependency. The computer and data services company can't provide its service until it has all the parts it requires. Purchasing components from a supplier is an example of an external dependency.
  

• milestones
  Milestones are the final input of activity sequencing. Milestones are significant events or stages in the development of a project. Some examples of common project milestones are:
  
  - initial research
  - concept development
  - design completion
  - prototype development
  - quality testing
  - final acceptance
  
  Milestones act as control points in long projects that have several work packages and smaller tasks. For example, the computer and data services company grouped the project deliverables to identify major project milestones. The milestones for the network project are: finalizing the product description; installing and configuring network hardware components; and testing network capabilities.
  
  Milestones need to be an input to activity sequencing to assure that the project meets all of the necessary requirements. It is important to identify milestones so that you can effectively measure the progress of your project.
  

Optimizing the sequence of project activities can help you to avoid costly delays and rework. When sequencing, you need to consider your activity list, product description, dependencies and milestones. By factoring these inputs into the sequencing equation, you will arrive at a more logical sequence, one that will allow you to sail through project development and implementation with fewer surprises and mistakes.