Functionality is a very broad concept, which can be defined as the degree to which a building supports the activities of its occupants. Simply put, office buildings should support office work, school buildings should support learning, and so on. The formulation of functional requirements starts with understanding user activities. What will people do in the building? What are the characteristics and nature of their activities? How many people are involved? Do activities involve the use of particular equipment? How are activities interrelated? These kinds of questions can be answered by analysis, observation and simply talking to people (see Techniques, page 94 for an overview of possible methods). The next step is to translate the insights gained into functional requirements concerning size and the quality of spaces. It is important to note, however, that an activity analysis does not automatically translate into functional requirements. For example, an activity like computer work comes with several obvious space-related requirements (enough space for a desk and a chair), comfort (enough light, not too noisy), and facilities (a reliable internet connection and coffee), but when one goes beyond such basic factors, the notion of functionality becomes more slippery and subject to rather intangible factors such as personal preferences and cultural norms and values. Is, for example, an open-plan office a functional solution or not? Different people tend to have very different opinions about this, which can make it challenge to establish what the right requirements are.For that reason, the formulation of functional requirements should not only involve a factual analysis of user activities, but also a dialogue with users about their perception of functionality. What is their notion of functionality? Where does that notion come from? How does it relate to their activities, the technologies they use, or the purpose of their organization?In this dialogue, it is important to focus on the need behind the need and not to jump straight into discussing concrete design solutions. This can be done by asking probing questions (e.g. why do you feel you need a private office?) aimed at eliciting the problems they want to have solved (e.g. too many distractions) before discussing any notion of a solution.Strategic brief-Describe the general activities that have to be accommodated in the building.-Identify distinctive or critical activities that will call for extra design attention.Functional brief-Draw up a concise description of how rooms and spaces will be used in daily practice (what activities, when, by whom, equipment required), insofar as this kind of information is not obvious. -Identify functional concerns (e.g. acoustics, security, privacy) which require extra attention and elaboration in the technical brief.-Look at the spatial relations between different functions and activities: which of them need to be close to each other, which need to be separated?Technical brief-Translate functional considerations into concrete specifications at room level, looking at finishes, fixtures, furniture, indoor climate and equipment.