What is CPM? | Definition, Uses, Advantages and Disadvantages

CPM, or the Critical Path Method, is a mathematic algorithm that schedules and designs project activities. CPM has been widely known to be used along with the Program Evaluation and Review Technique (PERT). The use of CPM has evolved over time and now refers to an analysis of project activities diagram.

By combining these two, a ‘critical path’ can be figured out for the completion of a project, which is the longest stretch of activities, containing the logical end points of the activities. By factoring in the earliest and latest times in which the activities can be started and finished, it can be used to determine which of the steps of the process are critical and which can be delayed without losing productivity.

The critical path in the field of project management thus refers to the longest network of activities which gives us the longest possible duration for completion. From here once can determine ways to increase productivity and reduce the overall time taken.

Different aspects of CPM

  1. A comprehensive list featuring all the activities involved in a project is required.
  2. The estimated time intervals necessary for beginning and completion of each task has to be calculated. Float refers to the delays which can be permitted without hampering the total project duration.
  3. Beginning and end points of activities and major milestones have to be figured out beforehand.
  4. The dependencies and interrelations between activities have to be clearly laid out.

Uses of CPM

CPM can be used in any and all projects which have interconnected activities. This includes but is not limited to construction projects, product, software, and research developments, engineering, and even aerospace and defence.

Advantages of using CPM

  1. It ensures improved and effective management techniques in any project. Efficiency is multiplied by several times through the use of CPM.
  2. A close monitoring of the schedule and a better understanding of the different components of a project ensures that the quality of management as well as work done is superior.
  3. By prioritizing certain critical activities the entire duration of the project can be curtailed and a lot of time may be saved. This is usually done in two ways:
  4. Performing more than one activity at the same time which are interconnected but do not influence each other in a major way.
  5. Shortening the critical path by adding more resources and thus saving more time.

Disadvantages of using CPM

  1. A lot of the variables that are fed into the structure are estimates which may vary to a great extent in practice. This includes not just the time for beginnings and ends of activities but also the resources necessary.
  2. As a result the actual progress may be stunted by quite a long while and the decisions taken based on the diagram drawn up may not yield desirable results.
  3. The critical path can be formed only when all the activities are logically interconnected to one another. This eliminates the scope of using CPM in several fields of work.
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  1. http://acqnotes.com/Attachments/Critical%20Path%20Method%20by%20Jesse%20Santiago%20&%20Desirae%20Magallon.pdf