It has been 30 years since the U.S. publication of the original 13-volume Grzimek's Animal Life Encyclopedia (1972-1975). Bernhard Grzimek served as director of the Frankfurt Zoo for more than 30 years and was also very active in the preservation of animal species in the wild as well as in captivity. In contrast to older works on animals, his encyclopedia, which was first published in Germany in 1967, was more concerned with animal behavior and conservation than with mere descriptions of appearance and habitat. In 1990 McGraw-Hill published a substantial revision of the four volumes of Grzimek's that dealt with mammals. Not only was the text of Grzimek's Encyclopedia of Mammals greatly updated but the set was graced with 3,000 color photographs that were created using new techniques for underwater, night, and action shots. The original 13-volume Grzimek's, meanwhile, went out of print. Since 1990 there has been a significant increase in reference materials on animals, in part because of a growing awareness of biodiversity and conservation. But even with this bounty, librarians have been waiting for a new edition of Grzimek's. Gale has stepped into the breach with a completely revised, 17-volume Grzimek's Animal Life Encyclopedia, of which the four volumes dealing with birds are the first to appear. Additional volumes will be released over the year.