When buildings don't perform as specified, occupants are often blamed for failing to change habits. According to Lester Shen, this is the wrong way to think about building efficiency. Shen challenges us to reframe our approach to high performance building via the concept of Human Building Interaction (HBI). HBI reveals assumptions, habits, and constraints that govern our relationship to buildings, and instead of forcing occupants to change, leverages existing behaviors to achieve performance objectives.