The purpose of the Ph.D. project has been to investigate how the sustainability agenda challenges building contractors' tendering processes, including how environmental sustainability initiatives appear in tender documents. Managing environmental sustainability requirements involves a wide range of uncertainties in an undefined and dynamic sustainability market with limited practical experience. More specifically, the project examines the devices that contractors use when creating, assessing, and rethinking environmental initiatives during the tendering process. The Ph.D. project draws on examples from DGNB, references, and value packages.