What is The Triple Constraint?

The triple constraint model (also known as the project management triangle, iron triangle and project triangle) shows the three parameters that determine a project and its success: Time, cost and performance or quality. These three objectives are symbolized by the corners of a triangle:

Triple Constraint
  • The time stands for the project duration and includes project start and end as well as all deadlines to be met that structure the project.
  • Costs refers to the budget that is set before the start of the project and should not be exceeded.
  • The performance of a project is determined by the objectives discussed with the stakeholders.

The 3 parameters are defined and prioritized before project start. The project control is then based on this.

If one of these variables changes, it has a direct effect on the other two variables. In order to achieve the project goals anyway, such a change must be compensated by the other two variables. This inevitably changes all three parameters.

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