We are very pleased to present a second edition of The Principles and Practice of Clinical Electrophysiology of Vision. It has been a considerable undertaking and has taken 5 years. We would like to take the opportunity to thank the authors who generously contributed their fine work and ideas. Most of the chapters have been rewritten, and many new topics have been added. As before, we have adopted the policy of having some differences of opinion between authors so that the reader will obtain the benefit of different points of view, and we have tried to cover a broad perspective, including historical introductions and a wealth of references for serious students. The first edition of this book sold out in 6 months, which would have been extremely gratifying to the editors and authors had the original printing been in a larger quantity! We now have a new publisher who has assured us that it is in the business for the long run and will keep up with demand. We are pleased with the publisher's track record in the field of neuroscience publication.

For the past 15 years, we have been asked repeatedly where any copy of the first edition could be obtained. The apparent demand for this material and the fact that there is indeed a great deal of new information in the field of clinical electrophysiology convinced us that we should try for a second edition despite the proliferation of online information. We have tried to include material that is likely to become more important in the next decade, in which period we hope that this edition will be helpful to workers in the field, both to orient themselves to what is new and to obtain a perspective of the subject and its remarkable development in the past century. In particular, we have added reports on multi-focal techniques, the recent advances in analysis of abnormalities in disease, and the applications of these techniques to the study of genetic abnormalities in humans and animals.

The high quality of this reference book directly reflects the expertise and broad knowledge of its authors, to whom full credit must be given. Each of them took time from very full schedules to contribute their chapters, and we thank them most sincerely. We would also like to thank the many colleagues who contributed to this base of data and made this volume possible. In addition, the editorial staff at MIT Press (especially Ms. Barbara Murphy) was most supportive and deserve all our commendations. The role of ISCERG/ISCEV should be acknowledged in providing organizational support for the development of the field. The field of clinical electrophysiology has come a long way since Karpe did his initial human studies in the 1950's.

 Geoffrey B. Arden

 John R. Heckenlively