Conventional building design assumes that occupants are passive recipients of indoor conditions, maintained within tight margins by automated, centralized systems. Building performance is typically invisible to the end-user, who – in turn – is given little opportunity to control or provide feedback on the indoor environment. In contrast, ‘green’ building design tends to view occupants as active participants, both in facilitating comfort and achieving optimal energy efficiency. This assumes that occupants have some understanding of the buildings they inhabit, and will make appropriate and intelligent choices when interacting with its systems (i.e. opening and closing windows, blinds, switches and other accessible manual controls). In practice, very little is known about how the occupants of green buildings engage in comfort provisioning and the subsequent impact this has on overall building energy performance. Research to date has focused on the residential sector, examining the decision-making behavior of homeowners around thermal comfort and electricity consumption. This paper describes a current research project which investigates, in a commercial setting, occupants’ knowledge of building environmental features and systems, and awareness of control and feedback opportunities available to them. A web-based survey has been designed to capture knowledge levels as compared to an expert baseline for six office buildings of varying degrees of energy efficiency. Preliminary results from the survey pilot are presented.