CCPM or Critical Chain Project Management has developed as a response to poorly performing projects. The issues considered include: outdated deadlines, frequently missed, with the increased costs in addition to the allocated budget.Some of the main conditions necessary for an efficient implementation of a project are:
CCPM or Critical Chain Project Management brings together the long periods of safety assigned to activities in buffer reserves to protect delivery times and to avoid wasting this safety time through:
The notion and idea of CCPM or Critical Chain Project Management was developed by Eliyahu Moshe Goldratt (March 31, 1947 – June 11, 2011) and was introduced in 1997 in his book Critical Chain. The book is actually teaching how to apply the Theory of Constraints (TOC) to project management.
In CCPM or Critical Chain Project Management are applied the TOC concepts to project management. First of all, the purpose of the whole system must be identified and in Critical Chain on-time performance is the primary goal when applied to one single project. If Critical Chain is applied to a multi-project then the main goal will be the throughput of the total system.
|The critical chain||The bottleneck resources that involve most cross-project utilization|
|Ensure that the activities in the critical chain are performed efficiently and there are no delays||Managing the deployment of the critical resources by prioritizing projects and avoiding multitasking|
|Critical activities from the critical chain must not be delayed or affected by non-critical activities||Ensure a high utilization of the bottleneck resources, including when this means that non-critical resources are left inactive.|
|Investment in additional resources||Investment in additional resources|
in this stage, the project is divided into tasks and each one is allocated a time interval and the necessary resources. The sequence of tasks that leads from the beginning to the end of the project and which is the longest in terms of resources is identified as the critical chain.
In Critical Chain Project Management, 50% of the estimated time is taken into account. For tasks that have the highest probability of not being completed on time, "buffers" are used. These are additional time intervals that together set a more plausible delivery date for the whole project. On average, these time buffers represent ⅓ the entire duration of the project. The difference between the time that includes the safety buffer and that 50 % of the initial estimate is the project deadline.There are 4 types of Buffer that are used in Critical Chain Project Management:
at this stage, all planning data is included in a chart called the fever chart. On the horizontal line is shown the time interval allocated to the project and the vertical line represents the time buffer. The latter is represented graphically in 3 colors, namely:
Because the initial planning of each task is estimated, the execution of each task is not followed in the planned time, but rather in the shortest possible time. At the same time, the existing time buffer is kept very carefully under control.