State departments of transportation (DOTs) and other transportation agencies across the U.S. are increasingly using alternative project delivery methods (APDMs) to deliver transportation projects and programs, besides the traditional design-bid-build (DBB) approach. Several factors are driving this trend, including the need to expedite project delivery, opportunities to identify and mitigate risks earlier in the project life cycle, shifting risks to or sharing risks with the parties most capable of managing them, and needing more projects to be completed within shorter periods of increased funding.

Numerous studies compare the cost and schedule performance of DBB and design-build (D-B) projects, and many of these same studies have attempted to compare the cost and schedule performance of DBB and D-B projects based on opinion-based data or small sample sizes. Research is needed on the impacts that transportation agencies may realize through the selection of the APDM best suited for particular projects, considering an agency’s needs or constraints. As the use of APDMs continues to grow, understanding the cost and schedule performance and risks within these methods is essential to improving procurement practices and maintaining the integrity of the selection process.

The project objectives are to (1) document cost and schedule benefits and risks associated with different APDMs, including D-B, progressive design-build (PDB), construction manager/general contractor (CM/GC), and public-private partnerships (PPP); (2) quantify the cost and schedule performance of APDM projects considering project type, size, and complexity, and (3) provide transportation agencies with guidelines for managing the risks associated with cost and schedule growth when implementing APDMs.