The traditional procurement method is the most common construction delivery method. This process begins with an owner selecting an engineer to prepare construction documents. These are prepared using drafting standards such as the NEC Engineering and Construction Contract. In most cases, the architect will release these construction documents publicly, or to a select group of general contractors, who will then place a bid on the project which reflects what they believe cost of construction will total. This bid is inclusive of a multitude of subcontractor bids for each specific trade. The general contractor’s fee is generally built into the bid cost. Most government contracts are bid competitively using this method.
Design-Build is a construction project delivery system where, in contrast to traditional "design-bid-build" the design and construction aspects are contracted for with a single entity known as the design-builder or design-build contractor.
Over the years, most major building projects have taken the form of design-bid-build, meaning an engineering firm designs it, the project owner puts it out to construction firms for bid and selects a general contractor, and then that contractor constructs the project. Design-Build is when an engineering firm and construction firm collaborates up front to present a bid to the project owner to design and build the project in a single package.This saves time, as it eliminates a step in the project sequence, and in many cases, construction on some phases can begin before the entire design process is complete. It can also reduce animosity between the engineering firm and contractor.