The MacLeamy Curve compares project effort versus influence and cost for IPD and design-bid-build. Which statement is true?

• A. It suggests IPD has less collaboration than traditional methods
• B. It shows IPD achieving greater influence earlier in the lifecycle than design-bid-build
• C. It is not used in IPD analysis
• D. It applies only to BIM processes

Answer: (B)

The MacLeamy Curve shows how the ability to influence project outcomes and the cost of changes shift depending on when decisions are made. In Integrated Project Delivery, the team works collaboratively from the earliest stages, sharing risk and aligning goals, so decisions that affect cost, schedule, and performance are made sooner. That early influence reduces the amount of costly rework later in the project, which is the point the curve highlights. By contrast, traditional design-bid-build tends to push key decisions into later phases, when changes are expensive and the team has less ability to steer outcomes. So the statement that IPD achieves greater influence earlier in the lifecycle than design-bid-build is the correct interpretation of the curve. The other options conflict with the curve’s premise—IPD is built on higher collaboration, the curve is a standard IPD vs. traditional analysis, and while BIM can support IPD, the curve itself is about delivery method rather than BIM alone.