Triple Constraint Theory In A Nutshell

The triple constraint theory argues that every project operates within the boundaries of cost, time, and scope. Importantly, these constraints are inextricably linked. When a business asks for a project to be completed in less time, this causes the cost to rise. When a business wants to save money on cost, the scope must be simplified or scaled-down.

Understanding the triple constraint theory

The triple constraint theory has been used in project management for over 50 years.

The theory argues that every project operates within the boundaries of three constraints:


Defined as the range, breadth, reach, spectrum, or dimension of the work to be done. Put differently, what work is being done and how much work is there?


Or the amount of time required to complete project tasks or the project itself.


Including resources related to labor, hardware, software, equipment, materials, and so on.

The triple constraint theory is a useful discussion point during client conversations.

Businesses use the theory to remind prospective clients that a project cannot be cheap, comprehensive, and fast at the same time.

In competitive industries where time is of the essence, it can also be used to set realistic expectations regarding cost and scope.

Additions to the triple constraint theory

While the theory has been a mainstay of project management for several decades, critics suggest that the three constraint model is inaccurate and impractical.

In response, the Project Management Institute (PMI) added a further three constraints:


What are the characteristics of the deliverable? Is it functional? Does it satisfy the needs or expectations of the stakeholder?

In the context of triple constraint theory, quality is a highly subjective term.

A new piece of software could have less functionality than was formally agreed upon and still be a success.

However, a car manufacturer that decides against its vehicles offering air conditioning will not be associated with quality by consumers in hot climates.


A significant factor in project management.

How does the business identify, analyze, and respond to risk? What level of risk is the project team willing to endure?

Establishing a project risk tolerance level then becomes one of the six constraints.


Represented by the value the project is expected to deliver to the organization and end-user.

If a project will not deliver benefits, then it should not be started.

If a project deliverable such as revenue falls below a predetermined limit, then the project should be stopped.

Here, the constraint is the point at which the business no longer deems the project viable.

Key takeaways

  • The triple constraint theory argues that every project is constrained by three inter-related factors: time, cost, and scope.
  • The triple constraint theory is a useful way to keep client expectations in check during the consultation process.
  • Some argue that the triple constraint theory is outdated and irrelevant for modern businesses. In response, three more constraints (quality, risk, and benefit) were added to the theory by the Project Management Institute.

Read Next: SWOT AnalysisPersonal SWOT AnalysisTOWS MatrixPESTEL AnalysisPorter’s Five ForcesTOWS MatrixSOAR Analysis.

Read Next: Portfolio Management, Program Management, Product Management, Project Management.

Connected Management Frameworks

Project Management

Project management is critical to any successful business venture, especially within startups. As the project manager, you will be responsible for developing and executing plans that ensure goals are met efficiently. You must also assess risks and anticipate issues to ensure projects move forward without interruption.

Program Management

Program management is a systematic approach to managing multiple related projects involving planning, organizing, monitoring, and controlling all aspects of the program to meet strategic goals by delivering value through coordinated efforts.

Project Management vs. Product Management

While a product manager focuses on ensuring a product fits the company’s overall business goals. A project manager ensures that the various projects within the organization are aligned with the business goals. Product and project managers often work hand in hand, however, with different goals, as the product manager oversees product development, whereas project managers oversee projects within the organization.

Change Management


Change Management

Change is an important and necessary fact of life for all organizations. But change is often unsuccessful because the people within organizations are resistant to change. Change management is a systematic approach to managing the transformation of organizational goals, values, technologies, or processes.

Kotter’s 8-Step Change Model

Harvard Business School professor Dr. John Kotter has been a thought-leader on organizational change, and he developed Kotter’s 8-step change model, which helps business managers deal with organizational change. Kotter created the 8-step model to drive organizational transformation.

McKinsey’s Seven Degrees

McKinsey’s Seven Degrees of Freedom for Growth is a strategy tool. Developed by partners at McKinsey and Company, the tool helps businesses understand which opportunities will contribute to expansion, and therefore it helps to prioritize those initiatives.

McKinsey 7-S Model

The McKinsey 7-S Model was developed in the late 1970s by Robert Waterman and Thomas Peters, who were consultants at McKinsey & Company. Waterman and Peters created seven key internal elements that inform a business of how well positioned it is to achieve its goals, based on three hard elements and four soft elements.

Lewin’s Change Management

Lewin’s change management model helps businesses manage the uncertainty and resistance associated with change. Kurt Lewin, one of the first academics to focus his research on group dynamics, developed a three-stage model. He proposed that the behavior of individuals happened as a function of group behavior.


The ADKAR model is a management tool designed to assist employees and businesses in transitioning through organizational change. To maximize the chances of employees embracing change, the ADKAR model was developed by author and engineer Jeff Hiatt in 2003. The model seeks to guide people through the change process and importantly, ensure that people do not revert to habitual ways of operating after some time has passed.

Force-Field Analysis

Social psychologist Kurt Lewin developed the force-field analysis in the 1940s. The force-field analysis is a decision-making tool used to quantify factors that support or oppose a change initiative. Lewin argued that businesses contain dynamic and interactive forces that work together in opposite directions. To institute successful change, the forces driving the change must be stronger than the forces hindering the change.

Business Innovation Matrix

Business innovation is about creating new opportunities for an organization to reinvent its core offerings, revenue streams, and enhance the value proposition for existing or new customers, thus renewing its whole business model. Business innovation springs by understanding the structure of the market, thus adapting or anticipating those changes.

Posci Change Management

According to Prosci founder Jeff Hiatt, the secret to successful change “lies beyond the visible and busy activities that surround change. Successful change, at its core, is rooted in something much simpler: how to facilitate change with one person.”

Read Next: Change Management.

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