The Iron Triangle of Project Management

Balancing Your Budget, Scope, and Schedule

(Also known as The Triple Constraint of Project Management.)

The Iron Triangle of Project Management

Learn how to deliver projects within the "iron triangle."

© iStockphoto/hanis

You're managing the implementation of a new reporting system for your organization.

As your project progresses, things happen differently from how you'd planned.

You find that you need extra computer hardware, and some tasks have taken longer to complete than you originally predicted.

To get the tasks completed on time, you consider recruiting more contractors. But, to do this, you'd have to take other costs out of the project's budget. You think about not buying the extra computer hardware that you need, however, this would mean changing the project's scope, so that some functionality isn't delivered.

In many projects, the budget, scope and schedule are closely linked. Changes to one of these three key constraints will most likely affect the others, or impact on the quality of the project.

This article examines the relationship between the three constraints of budget, scope and schedule, and looks at ideas and tools for helping you deal with the issues that can affect this relationship.

The Iron Triangle

The project mandate   and project charter   identify the project's objectives. At the core of these documents is a requirements statement that says what the project needs to deliver. This includes a definition of what is in and out of scope for the project. It also establishes the project's deadlines and its budget.

These constraints of scope, budget, and schedule are known as the "iron triangle" (see figure 1).

Figure 1 – The Iron Triangle of Project Management

The Iron Triangle of Project Management - Diagram

Original diagram in the article, "What is Project Management?" Reproduced with permission of the Association for Project Management.

These constraints are considered an iron triangle because you can rarely change one constraint without also impacting the others. The way that you deliver the project within these constraints impacts the quality of the project's outcomes, either positively or negatively.

For example, suppose your project mandate is to launch a new standalone IT system. The design phase has overrun significantly. You could consider several options:

... for the complete article:

Mind Tools Club members, click here.

Join the Mind Tools Club to finish this article AND get 1,000 more resources

Join now for just $1, first month

"When I started using Mind Tools, I was not in a supervisory position. Now I am. Along with that came a 12% increase in salary." – Pat Degan, Houston, USA
Add this article to My Learning Plan

Where to go from here:

Join the Mind Tools Club

Click to join Mind Tools
Printer-friendly version
Return to the top of the page

Create a Login to Save Your Learning Plan

This ensures that you don’t lose your plan.


Connect with…

Or create a Mind Tools login. Existing user? Log in here.
Log in with your existing Mind Tools details
Lost Username or Password
You are now logged in…

Lost username or password?

Please enter your username or email address and we'll send you a reminder.

Thank You!

Your log in details have been sent to the email account you registered with. Please check your email to reset your login details.

Create a Mind Tools Login
Your plan has been created.

While you're here, subscribe to our FREE newsletter?

Learn a new career skill every week, and get our Personal Development Plan workbook (worth $19.99) when you subscribe.


Thank You!

Please check your Inbox, and click on the link in the email from us. We can then send you the newsletter.