The paper examines how satisfaction with indoor environmental parameters and building features affects satisfaction and self-estimated job performance. The analyses used subjective responses from around 50, 000 occupants collected mainly in US office buildings using a web-based survey administered by the Center for the Built Environment (CBE) over the period of ten years. Overall satisfaction with the workspace significantly improved self-estimated job performance; increased satisfaction with temperature was estimated to provide the greatest improvement in self-estimated job performance, followed by increase in satisfaction with noise and air quality. The improvement of building features such as amount of space, visual privacy and noise level offered the highest chance to improve satisfaction with workspace. The study implies that it should be carefully considered how investments to upgrade indoor environmental quality and building design are used, and that they should consider whether comfort or working morale are expected to be improved.