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What is PERT: Definition, benefits, and tools

Updated on:
August 30, 2024
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The Program Evaluation and Review Technique (PERT) is a very important tool that is used in project management. The method is also useful in the planning and estimating of both time and cost of a particular project. Another tool, closely related to network diagrams, is a PERT chart which is used to create realistic time schedules and to control the resources. Unlike other techniques such as CCPM derived from WBS, PERT provides a mechanism for identifying the critical activities for scheduling and risk management to make a positive impact on the delivery of the project. Therefore, we can argue that PERT enhances the whole initiative of project management.

Introduction to PERT in project management

The Program Evaluation and Review Technique (PERT) is one of the most important tools that can be used in project management

It is mostly applied in planning and in particular scheduling of a project. It also helps in making proper time estimates and helps in making a better critical path network for the program. PERT breaks down the analysis of task estimations with the help of a network diagram which can be represented with the help of a PERT chart. Thus, PERT aids in cost estimation, and risk assessment and influences the management of resources with the aim of delivering the project on time.

Definition of PERT

PERT or the Program Evaluation and Review Technique is a project management tool used for mainly organizing, sequencing, and controlling activities in a project. Enhancing time estimates to the maximum level highly supports the timely completion of projects. This technique is closely related to the Critical Path Method (CPM). 

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A PERT chart is an alternative to a network diagram and is used to represent and schedule tasks. It helps in sound planning for projects by offering a way of addressing risks through determination of the project’s shortest possible time which does not affect the costs. As part of its strategy, it encompasses Work Breakdown Structure (WBS) and resources management.

History and development of PERT

The Program Evaluation and Review Technique (PERT) is a project management tool that was first employed by the US. Navy in 1958. It was intended to ensure the planning and coordination of large and often intricate military operations through the coordination of task estimations, risks, and schedules to support project implementation. 

That technique has advanced the practice of project management since it integrated time and cost estimation within a network diagram. The PERT chart, which stands for the Programme Evaluation and Review Technique, is derived from the Critical Path Method and the forerunner of the Gantt chart, shows the relations among tasks, and helped in the development of the WBS.

Understanding the PERT methodology

The Program Evaluation and Review Technique (PERT) is an important tool in managing a project depending on its application to structure the scheduling and time estimation of the activities within a project. PERT uses a diagram known as a PERT chart which is used to show the sequence of activities and the relations that exist between them. This technique is always linked with the Critical Path Method which enables the project manager to determine the longest series of activities that need to be done in order to complete the project on time. PERT can also be used for resource control and risk control since it makes probabilities based on the estimations of the tasks. Employment of the PERT methodology also entails the use of a Work Breakdown Structure that details the hierarchy of tasks and subtasks in the project hence enhancing the project planning and cost estimation.

Components of PERT: Nodes and arrows

The two major symbols used in the Program Evaluation and Review Technique (PERT) are nodes and arrows. These are either circular or rectangular shapes and denote events in project management. These are the events, which are in fact the milestones – the points when the tasks are initiated or finished, and which do not require or spend any resources or time. 

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On the other hand, arrows signify the activities or the tasks of the project. They show the order, the dependencies, and the flow of the tasks an important factor in time and cost assessments. These arrows point from one node to the next one, showing the sequence of the project, which aids in the scheduling and planning of the project. The PERT chart plays an invaluable role in defining the Critical Path Method, managing risks, and improving the manner and speed in which projects are delivered.

How PERT Works: The process explained

The Program Evaluation and Review Technique (PERT) is one of the most basic tools that are widely used in project management. In a way, it provides a graphic view of a project timeline using a PERT chart. It begins with the Work Breakdown Structure where the project is broken into sub-activities. 

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Subsequently, there are time and cost estimations for tasks or projects. The Critical Path Method is then identified with the help of the network diagram that PERT forms with the help of these data. This method helps in scheduling and risk analysis, and the focus is on the sequence of activities that have an effect on the delivery of the project. Therefore, PERT is an important tool when it comes to scheduling and resource allocation of projects.

The benefits of using PERT in project management

The following are the advantages of applying the Program Evaluation and Review Technique (PERT) in project management. Firstly, it helps in creating a work breakdown structure to plan the projects and it also helps in generating a network diagram. This makes it possible to have an accurate estimation of the tasks in a given project since they help in the estimation of time and cost. Secondly, PERT helps organize resources by defining the Critical Path Method. There is a way it assists in bringing out the important activities that are necessary for the timely completion of a project, hence resource appropriation. Finally, through risk assessment, PERT helps in managing the risks that are related to scheduling. Therefore, through the use of a PERT chart, the managers are in a position to predict and control potential problems and thereby control risks.

Enhanced project planning and scheduling

Improved planning and controlling of projects is essential in the management of projects. Tools like Critical Path Method, Gantt charts, and Work Breakdown Structure help in proper estimations of the tasks, time, and costs, and thus make the project’s completion easier. Some of the tools include the following; A network diagram can, for instance, give a picture of the expected progression of tasks. 

Such project planning tools together with resource and risk management form the basis of a credible PERT chart planning. The Program Evaluation and Review Technique helps in increasing the accuracy of predicting the timeline of a project.

Improved risk management

Risk management is also another crucial factor that is considered in the management of projects. Some of the practices include using the Critical Path Method in order to determine which tasks should be done first most especially when there are chances of running into a bottleneck. 

We also have to ensure that we sincerely undertake a cost and time estimate for each task, this can be made easier by the use of a work breakdown structure and other tools such as the Gantt chart of the PERT chart. The planning phase has to be always open for changes because there can always be some unexpected issues in the project. Some of these are effective resource management plans, schedule risk management, and consistent assessment of project performance. Consequently, it can be stated that project success is much more likely to be achieved by means of solid risk management.

Increased efficiency and productivity

There are tendencies that the application of such PM methods as CPM, schedules with the help of Gantt charts, and PERT can help to improve the results of the work and productivity. They also facilitate the accurate measurement of time and cost and efficient planning of the resources to be used. The Work Breakdown Structure is used in precise project planning and in breaking a project into subtasks for the purpose of task estimations. This improves on the handling of risk and significantly increases the pace of project delivery. This can be complemented by the use of network diagrams that can give a virtual map of the task dependencies and thus simplify the process. Keep in mind the following things: 

  • Increased Efficiency: These are CPM, Gantt charts, and PERT, which enhance the estimation of time and cost.
  • Enhanced Planning: The Work Breakdown Structure enhances the detail of the cost estimates and the speed of delivery.
  • Simplified Management: Network diagrams give the idea of task interdependence.

Limitations and challenges of PERT

As with other approaches, such as the PERT (Program Evaluation and Review Technique) typically used in project management, there are some drawbacks to this model as well. One weakness is the problem of providing adequate estimations of time, particularly for large-scale projects; this is due to the fact that PERT entails the provision of the pessimistic time, the optimistic time, and the most likely time. A disadvantage is the time and effort required in preparing PERT charts are more than what is required in preparing Gantt charts or the Critical Path Method. Finally, while PERT is useful in planning a project, it cannot easily incorporate dependency of activities since the network diagram fails to show this.

Complexity of PERT charts

PERT’s primary drawback is a detailed and, therefore, complex structure of the charts to be created. PERT chart as a project management tool was designed for project scheduling and time estimation and is based on the Critical Path Method. Although these charts are useful for the planning of resources and projects, they are very data-demanding and assume that the project delivery process is well understood. Besides, as compared to Gantt charts, the PERT charts are less easy to understand and analyze, thus making them more complex. Nevertheless, because they can precisely predict time and cost factors for implementation, they are a beneficial tool for risk management.

Uncertainty and estimation errors

In project management, it is possible to find such tools as the Critical Path Method or the Program Evaluation and Review Technique that can be very helpful for cost and time estimation. Nevertheless, the suggested methods are also accompanied by their level of uncertainty and possible estimation errors.

It is thus very clear that the degree of accuracy of a project schedule depends on the degree of accuracy of the estimates in the work breakdown structure. There is always a risk in estimating and this is the reason why there are always deviations in the project delivery schedule. Also, risk management is a critical function that minimizes uncertainties by predicting the existence of problems and developing methods to reduce their influence. While using the Gantt chart and the network diagram will go a long way in charting the project timeline as well as in the management of the different resources that may be required in the project, they cannot help but address inherent uncertainties. Therefore, it is always wise for the project managers to consider some flexibility in the planning process. Here are a few things to remember: 

  • Estimation Errors: CPM and PERT methods are informative but they contain possibilities of estimation errors.
  • Risk Management: This is important for controlling uncertainties as the problems are recognized in advance.
  • Visualization Tools: Still, planning is supported by Gantt charts and network diagrams but these cannot remove all unknowns.

Comparing PERT with other project management techniques

Like other project management techniques, PERT or Program Evaluation and Review Technique majorly deals with time and activity and time estimation. It offers the project tasks in a more versatile network diagram, a PERT chart that easily shows the order and dependency of tasks. This is especially useful when establishing the Critical Path Method, which is a work-flow sequence that has an impact on the delivery time of the project. Other techniques, for instance, the Gantt chart, focus more on the aspect of scheduling than on a network presentation of activities. On the other hand, WBS is more about chopping the project into more workable chunks, and more concerned with resources above all. PERT, Gantt chart, and Work Breakdown Structure are all tools for project planning and risk management and though each of them is valuable for project scheduling and risk management, PERT is the most valuable for projects where time is more important than cost.

PERT vs Gantt Charts

In project management, both PERT (Program Evaluation and Review Technique) and Gantt charts are planning scheduling and resource management tools. PERT chart is a network diagram derived from the critical path method that helps in the representation of the estimation of tasks which in turn helps in the estimation of time and cost. It is excellent in risk management by pointing out the key activities that may cause a delay in the delivery of the project. On the other hand, the Gantt chart prepared from Work Breakdown Structure is a horizontal bar chart giving the planning of the project schedule. It is most useful in determining the order of the tasks and also monitoring the progress of the project.

PERT vs Critical Path Method (CPM)

In the field of project management, there are two widely used approaches to project scheduling and time estimation, namely the Critical Path Method (CPM), and the Program Evaluation and Review Technique (PERT). These two techniques use a network diagram and assist in scheduling, cost control, and use of resources. CPM determines the sequence of activities that takes the project from where it is to where it has to be, and when each activity can start and finish and still not add time to the project. On the other hand, PERT is a statistical technique in project management, through which one is able to assess the activities that go with the accomplishment of a certain project, especially the time that is required in accomplishing each activity, and finally, arrive at the worst time for accomplishing the entire project.

Practical Application of PERT in project management

Program Evaluation and Review Technique (PERT) is therefore a useful tool in project management. It provides a good way of defining and timetabling activities in a project and how they may be sequenced and integrated. It helps in defining the critical activities through the Critical Path Method, guaranteeing the time estimate of activities is realistic. This technique can also be used in cost control since it describes the resources and amount of money that may be needed at each phase of the project. The PERT chart has been established to be an impressive chart for developing project plans. In particular, it allows a project manager to create a Work Breakdown Structure, with the dependencies of tasks shown in the network diagram. It enables one to manage risks by allowing one to identify areas that are likely to lead to slowness in the delivery of the project.

Using PERT for large-scale projects

The scale of a project usually entails a keen planning and control of the undertaking and a good estimation of the time to be taken. Program Evaluation and Review Technique (PERT) is ideal for this: I found that it is useful in visualizing project tasks, useful in presenting the schedule in a network diagram, as well as useful in highlighting the Critical Path Method. PERT chart is another important tool in project planning and helps in cost control and work breakdown structure. In addition, resource mobilization and risk management are well enhanced by PERT and thus lead to successful project completion.

PERT in Agile project management

In Agile project management, PERT is combined with other techniques such as the CPM, and the WBS. PERT chart is a primary tool in project planning and scheduling and all-time estimation of tasks and resources and risk assessment. From this detailed network diagram, the manager is able to determine the interdependencies of tasks and this will aid in identifying which tasks are critical and which are likely to cause bottlenecks. Finally, PERT is useful in Agile to guarantee the correct estimation of the costs and the completion of the project at the right time.

Top project management software with PERT capabilities

Microsoft Project is one of the best project management software that can support PERT. Some of the functionalities that this software has include time estimating, scheduling using the Critical Path Method, and Work Breakdown Structure. It enables you to develop a network diagram, Gantt chart, and above all, a PERT chart for the purpose of planning the project. The other is ProjectLibre and it is a free software with PERT features incorporated within it. This encompasses such areas as task estimates, cost estimates, resources, and risk estimates for the delivery of projects. Last but not least, Smartsheet also has strong PERT functions. Its PERT charts are as well interactive and give immediate representation of tasks in terms of their interdependencies for better planning of projects.

Microsoft Project

Microsoft Project is one of the best tools that are used for the management of projects. This is because it makes it easier to estimate the time required, and the cost to undertake the project and schedule the project. That is where it enhances the Critical Path Method of project delivery and risk management. Microsoft Project ensures that project planning is done in a way that includes the construction of network diagrams, construction of Gantt charts, and PERT charts in order to enhance the Work Breakdown Structure of a project. Besides, this software uses the Program Evaluation and Review Technique for the control of projects and helps in the management of resources. Microsoft Project provides the opportunity to make proper estimations of the tasks, which is a significant factor in the proper and effective functioning of the project management and its success.

Smartsheet

SmartSheet is one of the most effective tools for project management, as it offers many opportunities to plan and organize the project. These are for instance the Work Breakdown Structure, which is a potent tool in planning a project by dividing tasks into more manageable portions. SmartSheet is equipped with the options to create detailed network diagrams and Gantt charts, making the timeline of the project and the tasks easy to understand. The platform also contains specific tools, including the Critical Path Method for time assessment and scheduling, cost assessment for efficient resource utilization, and the Program Evaluation and Review Technique (PERT chart) for the assessments of the tasks. This suite of features makes risk management easier, thus enhancing the likelihood of successful project delivery by a great deal.

ProjectLibre

PojectLibre is one of the tools applied in project management that takes advantage of diverse techniques. It has features such as Critical Path Method, time estimation, and cost estimation and it therefore enhances project planning and accomplishment. Further, it employs various techniques for enhancing the understanding and implementation such as Work Breakdown Structure, network diagrams, and Gantt charts. Moreover, the PERT chart which stands for program evaluation and review technique is used in the task estimations to add more effectiveness to the process.

ProjectLibre also has resource management and risk management within its range, so that the problems with scheduling are smoothed out and a complete set of tools for achieving the goals of the project is provided. Here are a few terminologies that you should be familiar with: 

  • Efficient Planning: ProjectLibre employs the Critical Path Method for the planning of the projects.
  • Enhanced Visualization: It also has items such as the Gantt chart and the PERT chart to enhance the process of implementation.
  • Comprehensive Management: Expands resources and risk management to enhance the flow of the schedule.

Conclusion: The Power of PERT in modern project management

In present-day project management, PERT is a great tool, combining project scheduling, time estimating, and risk assessment to advance project implementation. If used in harmony, the network diagram, the Critical Path Method, and the PERT chart assist in keeping a proper flow of scheduling and cost-estimating. Moreover, the use of a Work Breakdown Structure, it makes possible to manage resources effectively. All in all, the PERT method has become one of the most effective identified strategies for managing projects and has become a primary technique used by project managers in today’s world.

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