Design-Build or Design/Construction Management-at-Risk is a construction project delivery system where, in contrast to traditional "design-bid-build" (or "design-tender"), the design and construction aspects are contracted for with a single entity known as the design-builder or design-build contractor. This system is used to minimize the project risk for an owner and reduce the delivery schedule by overlapping the design phase and construction phase of a project.

Design-build focuses on combining the design, permit and construction schedules in order to streamline the traditional design-bid-build environment. This shortens the time it takes to complete the project because the design-build firm will strive to bring together design and construction professionals in a collaborative environment to complete multiple tasks at the same time.  MWH is one of the few global organizations that can offer design-build fully facilitated by in-house staff.