Conditional Diagramming Method (CDM)

A third technique for constructing network diagrams is the conditional diagramming method (CDM).

Like other diagramming methods, the CDM uses nodes and arrows to represent the activities and dependencies in a project network. However, this method is distinguishable from other diagramming techniques by its loops and conditional branches.

Loops seen in the CDM indicate the repetition of activities in the activity network.

Conditional branches indicate options in a CDM diagram. The truth or falsity of a condition determines whether contingent activities will happen next.

For example, one phase of auto manufacturing involves painting the auto body. The activities that make up this phase may be outlined in the CDM diagram. In this case, the pass or fail condition of the painted auto body determines whether the auto body is delivered or redone. Delivering the auto body or redoing it are conditional branches or options dependent on the outcome of the pass/fail test.

In project management, the diagramming technique known as Graphical Evaluation and Review Technique (GERT) uses the CDM.

The conditional diagramming method is a technique that represents a network and shows the repeating and conditional activities in the project. This technique is valuable for helping you visualize and plan an activity's schedule. Using the CDM will help you to stay in control of the schedule which, in turn, will increase your chances of a successful project.