Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 71.This volume provides both a comprehensive geophysical, petrological, and geochemical background on mantle flow and melt generation at mid-ocean ridges and results of current research in the field. The first part of the book contains overview papers geared towards a broad scientific audience with the dual intent of introducing new workers to the field and providing useful background and reference for those who study different aspects of oceanic spreading centers. The second set of papers presents current research on mantle upwelling and melting beneath mid-ocean ridges.The motivation for publishing this set of papers as a monograph is to provide access to a range of currently recognized constraints and modeling approaches on the nature of mantle flow and melt generation along mid-ocean ridges. Our hope is that the multidisciplinary style of this volume will encourage communication between researchers in different fields and that this will enhance our progress towards a more complete understanding of the plate spreading and accretion process.