The main purpose of this guide to functionality in construction is to show how the 'functionality' of construction products can add value to business, so that it can become an intrinsic part of both the decision to build and the briefing process. The guide shows clients of the construction industry and their suppliers the importance of functionality in 'construction', where construction means all built facilities, including buildings and infrastructure. Functionality is about enabling things to happen, adding value to businesses and meeting personal aspirations. The guide includes details of steps which can be taken, and existing tools available, to enable functionality to be considered as part of the construction briefing process, and of the business review process. 42 pages.