This report provides an overview of publications by scientists at U.S. institutions between 1991 and 1994 on magmatic processes at ocean ridges. Study of the geochemical variations of the rocks that comprise the oceanic crust has become an integral part of multi-disciplinary approaches to the study of oceanic crustal genesis. These multi-disciplinary approaches link studies of geochemical variations of ocean ridge basalts, crystalline rocks, and peridotites to studies of mantle flow, melt generation, segregation and transport, and the tectonic processes that occur at the ridge axis. All of these processes control the chemical variations observed in the rocks that constitute the oceanic crust, and thus the nature of scientific investigation of compositional variations observed in rocks from the oceanic crust has become increasingly more diverse. As the following discussion indicates, substantial progress has been made over the past 4 years in documenting and understanding the nature and origin of the compositional variations observed in oceanic crustal rocks generated at ocean ridge spreading centers.