Developing a Network Schedule or Network Diagram

A Network Diagram is:

A Network Diagram is a visual flow diagram representing the sequence, interrelationships and dependencies of all activities that are required to be completed to complete of the project.

Work Packages from the Work Breakdown Structure (WBS) are used to build the activities found in the Network Diagram. An Activity can include one or more Work Packages and are placed in a sequence that allows orderly completion of the project.

The nodes on the Network Diagram represent the Activities, and the arrows depict the dependencies and the project flow.


  • A Network Diagram is constructed from a number of Activities, each of which are made up of one or more Work Packages
  • Work Packages are the primary input for developing a Network Diagram
  • All Activities that must be completed in order to complete the project
  • Work packagesare:
    • Defined independently of other work packages
    • Have a defined scope
    • Have definite start and finish points
    • May require specific resources
    • Include technical specifications
    • Include cost estimates
    • Are owned by an organisational unit
    • Belong to a single Cost Account. One cost account can have more than one Work Package associated with it
    • Do not include dependencies, sequencing, and timing
  • Well-developed Network Diagram should be easy to adjust when unexpected events occur while the project is under way
  • A Network Diagram provides the basis for scheduling labour and equipment
  • Network Diagrams enhance communication that melds all managers and groups together in meeting the time, cost and performance objectives of the project
  • Network Diagrams provides an estimate of the project duration
  • Network Diagrams identify the critical activities – those that should not be delayed