Although considerable research has been conducted to establish the performance of various adhesives under different conditions of service, much remains to be done. Of great importance are basic studies of the mechanisms of deterioration of adhesives in joints under known conditions so that reliable short-term performance tests may be devised to determine the expected performance of adhesives under various service conditions. Such research needs will undoubtedly be increased in importance by the continued introduction of new adhesives of different chemical types. In all probability, the nature of the adherend influences not only initial adhesion but also subsequent joint performance. Most experience reported here on permanence of joints has been gained with wood, but research on metal adhesives is also reviewed.