Stirling engine driven heat pumps are one of the most attractive potential products based on Stirling engines. Their many advantages in efficiency, fuel adaptability, quietness, compactness, controllability and potential for high reliability are well known. This paper briefly reviews these advantages, then turns to key technical concerns in Sterling engine driven heat pump development. These have been organized into an effective development program that will require about $4 million per year for 8 years to complete basic research, component development, and an estimated 3 generations of system hardware. The planning effort was directed by the Building Equipment Division of the DOE Office of Buildings and Communities Systems. 7 refs., 2 figs.