PM: Critical Path Analysis

A crucially important aspect of a project plan is its critical path.

Now that we’ve defined our detail level plan (covered in a prior post), it is time to perform critical path analysis. The objectives of this exercise are to:

• Confirm the accuracy of our plan by ensuring we have properly setup interdependencies between tasks resulting in the most realistic and shortest possible path to project completion.
• Establish a key tool to monitor, manage and drive our project to successful and timely completion.

Prior to discussing how to identify and analyze critical path, we’ll first cover what it is NOT! That is, critical path is not defined as the:

• Most important things to be done on a project
• Key product features
• Major milestones of the project

Any or all of the above may (or may not) be part of critical path, but they don’t in and of themselves define critical path.

According to PMI, critical path is defined as the, “…sequence of activities that represents the longest path through a project, which determines the shortest possible duration.”

As such, tasks on the critical path are called critical tasks because if they’re delayed, the entire project will be delayed.

Let’s now cover a simple example that clearly outlines critical path by making a bowl of oatmeal.

Critical tasks are those which are ABSOLUTELY required to prepare our bowl of oatmeal. The non-critical tasks are optional, even important, for a tasty bowl of oatmeal. However, due to the nature of non-critical path tasks, they will not hold us up if we hit an unexpected snag which would otherwise jeopardize timely completion of the entire project (in this case the making of our breakfast).

Based on this definition, we can now review our plan: to identify and pay special attention to those tasks on critical path to determine risks, mitigations to those risks and identify opportunities to shorten (or sure up) the overall timeline.

If we’ve properly set things up in our project planning tool (e.g., MS Project or Smartsheet) with end-to-end dependencies, these tools “can” actually identify critical path for us.

That said, we must realize that PMs manage projects, NOT tools. So, while I like the critical path identification capabilities in these tools, we MUST take the time to walk the plan (end-to-end) to ensure we didn’t miss anything. We do so by following each path of activity through the plan, like combing through a child’s hair, until we hit no snarls.

During this walkthrough, we’ll want to confirm that:

• Our dependencies (predecessors and successors) have been setup properly for each and every task.
• We haven’t placed something on critical path when it doesn’t need to be.
• Our estimates are reasonable and accurate.

As we perform this review, we will undoubtedly make updates. And, when we do so, we’ll again need to perform an end-to-end walkthrough of the plan until we can do so with absolutely no edits.

Know that everything in our plan does NOT need the same level of attention…

Now that the critical path has been identified, we are in a position to more effectively manage the plan by paying special attention to (a.k.a. laser focus on) those items. As such, when I’m doing my daily review of the plan and/or preparing for core team meetings, items on the critical path are at the top of my agenda. Secondarily, we’ll want to make sure items that weren’t previously on critical path don’t become so.

Performing critical path analysis ensures we have fully reviewed and tuned our plan for accuracy and are taking the surest and shortest path to project completion.

In closing, if you are looking to improve PM capabilities in yourself, or organization, feel free to reach out so we can discuss how I can help!

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