Obviously this guide could not have been produced without the cooperation of many people. Of over 450 individuals and scientific organizations contacted in 14 countries, 255 responded to our letters and well over 100 provided photographs for review and selection. We were particularly pleased that for the majority of the species found in the western North Atlantic our most difficult problem was narrowing the choices and ultimately selecting illustrations from the many good materials made available to us. Although there are far too many contributors to mention all by name, their prompt and enthusiastic responses to requests for help are gratefully acknowledged, whether or not their materials were used.

Although photo credits follow each figure, we would particularly like to cite the generosity of Marineland of Florida, Hideo Omura of the Japanese Whales Research Institute, J.G. Mead of the U.S. National Museum, K.C. Balcomb of Moclips Cetological Society, Seiji Ohsumi of the Far Seas Fisheries Research Laboratory, Jack Lentfer of the Alaskan Department of Fish and Game, the U.S. Naval Undersea Center (NUC), The University of Rhode Island, and William F. Perrin of the National Marine Fisheries Service (NMFS). Photographs by Taruski, McCann, Hain, Wheeler, and Rigley are in Winn's files. All others are in the files of Leatherwood and Caldwell. The illustrations for Figures B1 and D1 were prepared by George Galich of NUC. All other illustrations were prepared by Lois Winn.

The extensive and often tedious job of preparing black and white photographs of suitable format from the vast array of black and white and color negatives and prints and from color transparencies was accomplished at the NUC Photographic Laboratory by the able team of Domingo Sanchez, Ray Krenik, Jeanne Lucas, and Alan McPhee.

George E. Lingle and John C. Moore assisted with gathering and reviewing the literature and with cataloging and screening photo materials.

The various drafts of the manuscript were typed by Linda Thomson, Margaret Alvarez, and Sandra Nolan. Sandra Peterson assisted with proofreading the later drafts.

In preparing this guide we drew freely from the literature on cetaceans of this region and supplemented it with our own observations and with unpublished notes provided by our colleagues. A partial list of materials used, each a good source of reference material on cetaceans in general or on cetaceans of the western North Atlantic in particular, is provided in the following section, "Selected Bibliography."

All of the following colleagues read all or part of the manuscript and made useful suggestions for its improvement: K.C. Balcomb, W.C. Cummings, J.G. Mead, Hideo Omura, W.F. Perrin, F.K. Rodgers, Allen N. Saltzman, D.E. Sergeant, W.A. Watkins, A.A. Wolman, and F.G. Wood.

All of the information and photographs contributed by Lois Winn were obtained under grants from the Office of Naval Research. Funds and assistance for the preparation of intermediated drafts and logistics support for all stages of preparation of this guide were provided by Biological Systems, Inc., St. Augustine, Fla.

In addition to securing funds for the preparation and publication of this guide, Paul Sund, Platforms of Opportunity Program, NMFS, Tiburon, Calif., provided continuing help and criticism.

To these and to all who use this guide to further help knowledge about the cetaceans of the western North Atlantic, we are grateful.