This study highlights valuable findings on the thermal comfort and livability of passive solar homes. These buildings are a sample of 335 homes that incorporate early passive solar designs. The data collection effort consisted of a performance audit conducted by trained auditors and an occupant questionnaire completed by the passive solar homeowners on their perceptions, experiences, and demographics. The questionnaire and audit technique coupled with utility bills were used to establish a data base of both quantitative and qualitative information on the performance of these passive solar homes.