A project network diagram is a graph that displays the order in which a project’s activities are to be completed. Derived from the work breakdown structure, the terminal elements of a project are organized sequentially based on the relationship among them. It is typically drawn from left to right to reflect project chronology.^[1]

Techniques

Activity-on-Node

The Activity-on-Node (AON) technique uses nodes to represent individual project activities and path arrows to designate the sequence of activity completion.^[2] Nodes are labelled using information pertaining to the activity. According to Project Management, nodes should at least display the following information:^[3]

• Identifier
• Descriptive label
• Activity duration
• Early start time
• Early finish time
• Late start time
• Late finish time
• Activity float (slack)

Start and finish times are used to determine the critical path of a project. Activity float, or slack, time is used in project crashing.

Other techniques

The condition for a valid project network is that it doesn't contain any circular references.

Project dependencies can also be depicted by a predecessor table. Although such a form is very inconvenient for human analysis, project management software often offers such a view for data entry.

An alternative way of showing and analyzing the sequence of project work is the design structure matrix or dependency structure matrix.