With a Design & Build agreement, the client concludes one contract with one partner who is responsible for the implementation of both the design and the construction of the project. Since the design and construction are carried out by a single contractor, the client has only one point of contact. By involving the contractor in the design and construction process at an early stage, the client receives advice more quickly on the design, costs, planning and various construction options for his project. This offers the client the opportunity to better estimate the project costs, the project size and the delivery date and to review and adjust if necessary. Since the design and construction process are carried out by one party, the design and construction phases can overlap. 

Considerations and benefits:

1. This form of collaboration is often used in projects where the design-build team has a great deal of experience with the type of project (industrial, apartment, office building, care housing) or where a certain specialization is required.

2. Before the client enters into a Design & Build agreement with a contractor, the client is obliged to provide the contractor with a preliminary design and planning idea, as he sees it. 

3. The client receives information about the cost estimate at an early stage, sometimes even during the conceptual design.

4. The client can use additional services such as: 
          Feasibility studies
          Valuation
          Life cycle costs
          
5. A lot of time is saved because construction can start before the design is finished.

6. Architects' and engineers' fees can be reduced through the early involvement of the design-construction partner/contractor.

7. Construction costs are minimized by including evaluation moments at regular intervals. In addition, the contractor knows his trade, he knows which materials, construction methods and systems are more cost-effective. 

8. Misunderstandings between the parties are minimized when the client and designer-contractor work together as a team during the planning phases of the project. Communication can go well as there are only a few parties and everyone is involved from the start. 

9. The risk to the client is minimized because the team approach of the design-build team focuses on early detection and resolution of problems.