The ejector-compression refrigeration system, a heat powered system which can be operated as a heat pump, is described. The operation of the system is discussed in general and the ejector itself is described in more detail. The central thrust of the paper is the application of the system to comfort air conditioning of automobiles. The advantages, limitations, and recommendations for future research and development are given.Several analyses of the theoretical cycle are made and equations describing the operation of the ejector are derived. A brief bibliography is listed.