Intense interest in GMR has developed world-wide because of the combination of an exciting basic phenomenon and its demonstrated importance in read-heads for magnetic storage. We have a variety of efforts in this area, including studies of GMR in heterogeneous thin films with metallic and insulating matrices, micromagnetic modeling of GMR devices, basic studies of spin relaxation in thin films, new GMR thin film configurations (spin-valves), exchange interactions among ferromagnetic clusters in heterogeneous GMR films, and the enormous "intrinsic" GMR exhibited by some perovskite materials. We are also studying spin-dependent tunneling in tunnel junctions and discontinuous multilayers which offer the promise of the high field sensitivity essential to many applications.