The mysterious critical path notion seems to put project managers in difficulty and especially the novice ones. However if anyone would take just a few minutes from his precious time to pay a closer attention to it things would be a lot more clear.
In order to clear things up we need to have a background knowledge. On short it all started with the Critical Path Method (CPM) an algorithm for scheduling activities within a project. This method is best used within the project scheduling phase and basically it requires to construct a model of the project that includes:
- the list of activities needed to complete the project (aka Work Breakdown Structure defined in the project planning phase)
- the duration estimates for these activities
- the dependencies between the tasks
There are two possibilities to render the structure created according to CPM: activity on arrow and activity on node. The most used representation nowadays is the activity on node. The activities are rendered as nodes and each node contains the duration of that activity while the dependencies are rendered as arrows where the arrowhead points to the successor while the tail to the predecessor.
To some extent a Gantt chart can also be considered as a CPM presentation although a more complex one. (more…)