The ‘Critical Path’ is a sequence of connected tasks without any slack time (or ‘float’) between them. These tasks form the longest consecutive sequence of tasks in the project and thus determine the finish date of the project. Due to the lack of any slack time between tasks in the critical path, any deviation in one task causes a deviation in the project as a whole. Therefore, the project manager must monitor the critical path continuously, as well as other project paths with slack times that shrink gradually possibly creating a new, longer critical path.
In the critical path control processes, it is important to emphasize three aspects:
- The start date of the tasks that are in the critical path of the project;
- The ongoing progress of work in these tasks;
- Their completion date.
To ensure that tasks in the critical path begin on time, it is important to provide an alert ahead of the expected start date of these tasks and ensure that the resources needed to perform them are prepared and ready to begin the work required of them.
Since the critical path can change due to the actual progress of the project, keep track not only of the actual critical path but also of is the one known as the ‘almost critical’ path, which results from shrinking overall slack times. Controlling the almost critical path demands focus on the overall slack times of project tasks, so that warning can be given whenever these are shrinking to the point where a new critical path might be created, thereby generating a new project finish date.