Design brief. A design brief is a written document for a design project developed in concert by a person representing the business need for design and the designer. The document is focused on the desired results of design – not aesthetics. Design briefs are commonly used in consulting engagements, when an independent designer or a design agency executes a design on behalf of a client. They are less common when the designer is in-house. it is commonly used in Environmental Graphic Design, in schools across the world. Design briefs are part of the design functions of companies and corporations, especially architecture, graphic design, product design and engineering firms.