This book is based on presentations given at CGRP '98, the Third International Meeting on CGRP and related peptides held in the UK in May 1998. The principal speakers have each contributed a chapter and many of the short and poster communications will also be found here. This book follows from the tradition set by the First and Second Meetings in 1992 and 1995 when the proceedings were published. The work is aimed at the specialist in the field, but it is hoped that many of the chapters will also prove useful as introductions to those wishing to gain greater familiarity with the biology and pharmacology of these important peptides. The book begins with a broad overview of the field, past and present. It is followed by two chapters dealing with the "classical" pharmacology of CGRP. In particular there is an account of the pitfalls of the present generation of CGRP antagonists and the dangers of assuming that every action of CGRP is mediated by a CGRP receptor. However the bulk of this section is taken up by the recent developments concerning the cloning of receptors for CGRP and adrenomedullin. An exciting story is emerging of how a single molecule, calcitonin receptor-like receptor (CRLR), can mediate the response to both CGRP and adrenomedullin depending on the presence of different members of a family of accessory proteins, the Receptor Activity Modifying Proteins (RAMPs). This is covered in three chapters and is followed by an account of another accessory protein associated with CGRP responsiveness, Receptor Component Protein (RCP). Following sections of the book deal with the biochemistry, physiology and pharmacology of receptors for the allied peptides amylin and adrenomedullin. The close connections between amylin and calcitonin receptors are highlighted and role of amylin in the regulation of food intake is then considered. The molecular nature of adrenomedullin receptors is addressed in an earlier chapter but in this section their pharmacology is examined. The pathophysiology of CGRP and related peptides formed a significant part of the meeting. Three chapters examine the role of CGRP in vascular disorders, joint dysfunction and gastrointestinal pathology. A separate section considers the role of CGRP in headache and migraine. The book concludes with a selection of the short oral and poster communications and then an important appendix, reflecting a workshop held to discuss the nomenclature of CGRP, amylin and adrenomedullin receptors. As the majority of the active workers in the field were present at this meeting it is hoped that the consensus view presented here might be widely acceptable.