The present volume is as much a book co-authored by all the contributors as it is an edited collection of their papers. Most of the contributors have been involved in regular discussions over the past years, often inspiring the questions, or some aspects of the proposals, in each other's papers or actually collaborating on co-authored papers. ! For this reason, the contributions make related assumptions and explore highly related issues. The organization of the volume reflects this unity of aims and interests. It starts out with an overview of some of the shared formal background, and the chapters are arranged in a sequence that is intended to invite the reader to proceed from one directly to the next. Nevertheless, there has been no attempt to eliminate individual differences in either assumptions or choice of topic. All the chapters are entirely self-contained, so the reader will find it equally possible to read any of them in isolation. Two members of the UCLA community do not appear in this volume but have been an important source of inspiration for this project: Ed Keenan and Feng-hsi Liu. Many of Keenan's works have drawn attention to the empirically diverse behavior of natural language determiners and developed theoretical tools for studying them. Liu's 1990 dissertation examined the abilities of a representative sample of noun phrases to participate in scopal dependencies and branching, coming up with provocative generalizations and pointing out their significance for then-standard theories in powerful terms.