Recent research suggests that buildings with operable windows in general, and mixed-mode (MM) buildings in particular can provide improved thermal comfort and control opportunities for users. Yet, there have been concerns about outdoor noise sources like traffic or construction noise when windows are opened. Concerns like these may hinder the installation of operable windows in buildings. This paper examines 23,000 office building occupants' perspectives on noise from both sealed and naturally ventilated/MM buildings. Results suggest thatoccupants near operable windows are more satisfied than those near sealed windows or those far from either window type. Among occupants dissatisfied with noise, complaints about indoor noise sources --like people talking-- are about 10 times more prevalent than outdoor noise complaints