What is Critical Path in Project Management?

If you are facing challenges in identifying the Critical Path in your Project, you have found the perfect guide. This article covers every insight on the Critical Path, the method to find it along with importance. By the end of this guide, you will be able to easily find the Critical Path to manage your project activities.

Project Managers often find it challenging to accurately determine the tasks and activities for executing the project plan. This is important not only for meeting the stakeholder expectations but also for managing the project quality from the end-users perspective. However, planning these activities can be done in more than one way. Or, we can say there are multiple paths for the project tasks.

But out of these, which path is Critical for our Project? In this article, we will learn about the Critical Path, one of the most important topics of Project Management. So, let us get started without any delay.

What is the Critical Path Method?

The Critical Path Method (CPM) is the process of finding the Critical Path in our Project. It includes identifying the tasks and activities, estimating their completion time, and then finding the longest sequence of tasks.

1. It not only tells us about the timeline of the tasks but also tells us their priority.
2. The CPM method allows the Tasks to be labeled as Critical and Non-Critical Tasks.
3. The Critical Tasks are the tasks which have to be scheduled without any delay.
4. On the other hand, Non-Critical Tasks are flexible and their timeline can be extended.

Benefits of using Critical Path Method in Project Management

Once we find the Critical Path, we do not need to further worry about the Project tasks, deliverables, and timelines. We just have to focus on the execution of the tasks by utilizing the allocated resources. Moreover, it helps us to deliver the required business value to the stakeholders by focusing on the key activities. Other than this, the following points tell us about Critical Path’s benefits.

1. Helps to measure project performance: Using Critical Path, we can measure project performance against the expected project quality. In this way, we can find deviations from the critical path to address them.
2. Helps in risk management: Project managers can focus on potential risks and issues before they impact the project. Hence, they can implement the risk response strategy quickly.
3. Helps to enhance project timelines: It allows the project managers to enhance the project timeline by identifying the longest sequence of activities. This is done by properly allocating resources to meet deadlines.

For identifying Critical, there is a series of steps that have to be followed. It is called the CPM. Let us learn about this process of identifying the Critical Path in Project Management.

Steps to find Critical Path in Project

Step 1: Identify All Tasks

Before finding the Critical Path, the tasks need to be defined. In this step, all the tasks, activities, or processes are defined which are required for the completion of the project. This list of activities is called the Work Breakdown Structure. It works like a high-level idea that guides the team about what task to perform and how to perform it.

Step 2: Determine the Sequence

Once you are clear with what to perform and how to perform it, you have to identify when to perform the tasks. Hence, in this step, you have to establish the sequence of the various tasks and activities identified in the previous step. This allows us to understand the logical flow of the activities which helps us in creating the network diagram.

Step 3: Estimate the Duration of Each Task

Here the project experts conduct discussions with the team and stakeholders to calculate the estimated duration of each task in the sequence. The duration of the task includes the total time from the start to the completion of the task. It is important to understand that every task duration contributes to the entire project timeline.

Step 4: Draw the Project Network Diagram

Now, you have to create a Project Network Diagram for project tasks. A Project Network Diagram is the visual representation of the tasks in which the nodes represent the activities and arrows denote dependencies among them. Network Diagram can be of different types such as the Arrow Diagram Method (ADM) or Precedence Diagram Method (PDM).

Step 5: Identify the Critical Path

You are now ready to look for the Critical Path in your Project. In this step, the longest path that passes through all critical tasks is chosen. In Critical Path, all the essential interdependent tasks are included so that, need to switch to different paths. This is the reason why Critical Path has the minimum completion time in the Project.

Step 6: Calculate the Float

As we discussed in Step 1, tasks can be critical as well as non-critical. Since the Critical Tasks cannot be extended, their delay time(also called Float or Slack) is zero. But on the other hand, non-critical tasks can be extended. Thus, they have some positive Float Value. The Float Value is the difference between the earliest and latest start or finish point of the task. You have to find the Float value to adjust the delay of non-crucial tasks.

Step 7: Monitor the Critical Path

After you are done with all the steps, you now have to continuously monitor and review the entire critical path. The project professionals have to track progress, manage the resources, and handle the unwanted delays in the project. This step aims to maintain the project schedule so that we can deliver it within the timeline.

Critical Path Method Example

The definition of the ‘Critical Path’ completely aligns with its name as it outlines the set of activities that are crucial for the Project. Let us understand this using an example. Suppose we have to organize a Workshop on Project Management.

We have to identify the various activities to organize them in a minimum time. Hence, we can use CPM to schedule the project activities with accuracy and precision. Also, it makes sure that project professionals allocate the resources to various project processes with efficiency.

Example of Critical Path

In this example, the Critical Path represents the most optimal way to identify, organize, and manage the project activities. This will help the users to focus on the most important aspects of the projects.

Critical Method Vs PERT Method

Apart from the Critical Path Method, there is another method called Project Evaluation and Review Technique (PERT) which you can use to schedule your project. The main difference between the two is CPM is mainly based on the deterministic approach to finding critical paths. On the other hand, PERT is a probabilistic method that defines the sequence of tasks using the probable time. It has three measures namely Most probable, optimistic, and pessimistic to find the duration of tasks. The following table highlights the key difference between the CPM and PERT method.

Parameters	CPM	PERT
Definition	It is a Deterministic approach with a single-time estimate.	It is a Deterministic approach with a single-time estimate.
Focus on	It has Limited emphasis on handling uncertainty.	It addresses uncertainty through a weighted average formula.
Identifies	CPM identifies float as the time difference between early and late start times.	It considers float but often focuses more on the critical path for project control.
Suitable for	It is well-suited for projects with well-defined activities and limited uncertainty.	This method is preferred for projects with high uncertainty and complex, non-repetitive tasks.
Approach type	It is a simple approach.	It is more complex with the statistical analysis and probability distributions.

CPM Success Story

At present, the CPM method is used in managing projects related to different industries. However, its success story dates back to the years 1931-1936 during the construction of Hoover Dam.

1. The Critical Path Method was not formally defined but its principles were used in the construction project to plan and schedule the tasks. The Construction was similar to a normal project with different interdependent tasks and activities. Thus, CPM helped the Project Managers to manage these activities within the timeline and budget.
2. It also helped to prioritize the tasks. As a result, the dam was successfully constructed two years before its deadline. Hence, the credit for success goes to the Critical Path Method. Later in the 1950s, Morgan R. Walker and James E. Kelley formally defined the principles of CPM to handle the complexities of the project.

This is how CPM evolved and became a popular tool in Project Management.

Case Study: Real-World Application of Critical Path Analysis

The core part of the Critical Path Analysis involves creating an accurate project schedule so that the flow of execution remains smooth. There are various examples in which the Critical Path Analysis proved its utility. Following are the real-world applications in which CPM was used as the main tool to manage the project.

1. In the year 1969, the Apollo Project to land on the Moon used the CPM method to complete the tasks on time and within the budget.
2. The project of expanding the Panama Canal, planned in the year 2016 required multiple stakeholders to collaborate. Thus, they used Critical Path Analysis for successful project delivery.
3. Not only this, but the London Olympics also took advantage of Critical Path in the year 2016. It project aimed to deliver 200 Projects and 10,000 suppliers for Sporting events. This was made successful because of CPM.

Challenges and Limitations

CPM is easier to implement, but every crucial concept in Project Management may have some challenges. These need to be tackled while using it to manage our project. Let us discuss these challenges and limitations so that we can easily overcome them.

Challenges of Critical Path in Project Management

1. We have to maintain a clear project schedule: The users have to maintain a clear project schedule of current tasks so that we can focus on the key activities that directly impact the project timeline.
2. The upcoming schedule must be planned: The project professionals should reliably predict the project timeline which helps them in planning the upcoming project schedule ahead.
3. Users should allocate resources accurately: CPM should be used with the proper resource allocation. The critical tasks should be given priority in terms of resources so that we can precisely utilize the resources. Otherwise, the project will suffer failure.

Limitations of Critical Path in Project Management

1. It is less flexible for uncertainties: Since CPM has fixed estimates, users face many challenges in adapting to uncertain circumstances.
2. It ignores the resource limits: CPM mainly focuses on timeline management due to which overallocation of the resource can occur. This will further lead to unbalanced project execution.
3. It is highly dependent on the input data: The main inputs for the Critical Path method are the task durations and dependencies. If any of these are inaccurate, the entire steps of Critical Path suffer and at the last, project execution also faces the issues.

Conclusion

The Critical Path is the longest sequence of tasks but with the minimum completion time. Hence, it is important to efficiently schedule the project activities. It focuses not only on the essential tasks but also on the non-critical tasks. This allows the project managers to manage the timelines according to the priority of the task and evaluate the impact of delaying the task. We hope that you have gained a clear understanding of Critical Path in Project Management and how to find it. You are now able to adopt the proper sequence of tasks in your project.

FAQs

1. What is the difference between the Gantt Chart and the CPM Method?

Gannt Chart and CPM both are Project Management concepts but they are different from each other. Gannt Chart is a visual tool and CPM is a Project Management technique. Gantt chart shows the timeline of each project task including their start date, end date, progress, etc. However, the CPM not only shows the timeline of project tasks but also shows the dependency of the tasks across multiple paths.

2. Can the team change or update the Critical Path during the Project?

We often have to face modifications, updates, changes, or delays in the tasks. Due to this, the Critical Path of the Project may be affected. We can change the Critical Path of our Project by reframing the tasks and their priority.

3. What are the rules for drawing the Network Diagram?

The rules to create the Network Diagram are very simple. Firstly, the Network diagram must have only one start node and one end node. Secondly, there should be no loops in the diagram. Also, the Node in the Network should contain the duration of the task and precedents (previous activities).

4. What are forward pass and backward pass in the Network Diagram?

Forward Pass in the Network Diagram calculates the Earliest Start and Finish of the Task that is calculated in the project start. And, Backward Pass calculates the Latest Start and Finish of the Tasks which is estimated when the end of the project appears.