What Is the Project Management Triangle?

The project management triangle is a visual representation of the three basic aspects that must be considered and managed for any type of project or business endeavor. These three aspects are: cost, in terms of financial costs; time, with reference to the amount of time needed to complete the project; and scope or quality, which indicates the end result of the project or the quality of that result. The project management triangle is often used to not only indicate these three aspects of a project, but to also demonstrate how they relate to and influence each other.

Also called the scope triangle or triple constraint model, the project management triangle is often represented as an equilateral triangle. The three sides or the three points are labeled with the three different aspects of a business project. The purpose of the project management triangle is to provide a visual method by which a project manager can more easily understand the three underlying aspects of a project.

Both time and cost are fairly simple and straightforward aspects of the project management triangle. They each represent the amount of resources, in terms of financial costs and time, which need to be spent on a project to see it through to completion. The third point or side of the triangle, scope, can be a bit more complicated.

Scope typically refers to the overall nature of the project and what is to be completed over its course. If a company is producing a new word processing computer program, for example, then scope would refer to the finished program and all its features. Scope, on the project management triangle, can sometimes be exchanged for quality. In other instances, the two are separated and quality is presented as a fourth side, creating a diamond instead; scope can also be replaced by “product,” which then represents both “scope” and “quality.”

One of the major benefits of using the project management triangle is that the visual representation demonstrates how these three concepts are interrelated. Whenever one side of the triangle is changed, an increase in scope for example, then at least one of the other sides must also change. The increase in scope or quality typically requires an increase in either time or money, or both, and this is represented by how the overall shape of the triangle must change whenever one side is changed. Some of this symbolism becomes lost through the use of a diamond or other shape, and so the project management triangle is still often taught and used in business.