Scope, Schedule, Resources: Pick Two

The project management triangle is one of the most fundamental concepts in project management, yet it's constantly ignored.

The Iron Triangle

Every project has three constraints:

• Scope: What you're building
• Schedule: When it needs to be done
• Resources: What you have to work with (people, money, tools)

The Reality

You can optimize for two of these constraints, but the third will suffer. This isn't pessimism—it's physics.

Common Scenarios

Fixed Scope + Fixed Schedule

Resources become the variable. You'll need more people, more money, or more tools.

Fixed Scope + Fixed Resources

Schedule becomes the variable. It will take longer than you think.

Fixed Schedule + Fixed Resources

Scope becomes the variable. You'll need to cut features or reduce quality.

The Fourth Dimension: Quality

Some models add quality as a fourth constraint. In reality, quality is often the first casualty when the triangle is ignored.

Why This Matters

Stakeholder Expectations

Understanding the triangle helps set realistic expectations with stakeholders.

Resource Planning

It forces honest conversations about what's actually possible.

Risk Management

It helps identify where problems are likely to emerge.

Common Mistakes

The Triple Constraint Myth

Believing you can have all three constraints fixed without consequences.

Scope Creep

Adding features without adjusting schedule or resources.

Resource Starvation

Expecting the same output with fewer resources.

Making It Work

1. Be Explicit: Make the constraints visible to everyone
2. Prioritize: Decide which constraints are most important
3. Communicate: Keep stakeholders informed about trade-offs
4. Adjust: Be willing to modify constraints as you learn more

The Bottom Line

The triangle isn't a limitation—it's a tool for making better decisions about your project.

Accept the triangle, work with it, and your projects will be more successful.