This paper investigates the Indoor Environmental Quality (IEQ)-related components of the LEED and BREEAM environmental assessment tools for new buildings. The analysis showed that both methods have a number of possibilities for improvement concerning the IEQ; (1) the available credits are not evenly distributed, (2) some sub-aspects are missing, and (3) in-use assessment of buildings is not mandatory. The IEQ-related chapters of both LEED and BREEM should be reevaluated by experts in the field of IEQ to ensure that a rated green building provides a high-performance IEQ. Also, inuse assessments are a valuable tool to ensure performance over a longer period of time and should be made mandatory for rated buildings.@en