Design-build is a Project Delivery System in which the design and construction services are contracted by a single entity known as the design-builder or design-build contractor. In contrast to "design-bid-build" (or "design-tender") where an architect is hired separately and often provides incomplete or ambiguous plans and specifications to the general contractor (who is also hired separately), design-build relies on a single point of responsibility and is used to minimize risks for the project owner and reduce the delivery schedule by overlapping the design phase and construction phase of a project.
In the Design-Build contract the construction team is known as the design-builder. They are responsible for taking a concept developed by the owner, completing the detailed design, and then pending owner’s approval on the design, proceed with the construction.
The traditional approach for construction projects consists of the appointment of a designer on one side, and the appointment of a contractor on the other. The design-build procurement route changes the traditional sequence of work. It addresses the clients concerns and aspirations for a single-point of responsibility in an attempt to reduce risks and overall costs. It is now commonly used in Canada because it is a win-win situation for all parties involved in a Contract.
Design-Build is sometimes compared to the "master builder" approach, one of the oldest forms of construction procedures. Comparing design-build to the traditional method of procurement, the authors of "Design-Build Contracting Handbook" noted that:
“ from a historical perspective the so-called traditional approach is actually a very recent concept, only being in use approximately 150 years. In contrast, the design-build concept - also known as the "master builder" concept - has been reported as being in use for over four millennia."