The Triple Constraint in Project Management

Abstract

Time, scope and cost are the key constraints when managing a project. These three interdependent constraints forms what is known as The Triple Constraint or The Iron Triangle. During the project's life cycle it is the project managers job to balance between the key constraints to obtain trade-offs within a reasonable limit to obtain a successful project. This model implies that the project quality or successfully completion is affected by the trade-offs performed and it is the project managers job to know how the three constraints interrelate. The model however does not determine success. The model has been widely used since the 1950s and the application and limitations has been discussed extensively. Atkinson, is one of the critics who claims the model is insufficient for determine the project success, because success rely on several additional factors and not only the three constraints . Others are more positive, but in general it seems that many would like to modify the model to improve the interpretation . The aim of this paper is to explain the concept of the triplet constrain and it's application and limitations in project management and to reflect on the different perspectives.