Book excerpt: Featuring nearly 400 clear, sharp photomicrographs, the Third Edition of this primer is a user-friendly guide to interpreting skin biopsies. Abnormalities are grouped according to location in the skin and morphologic characteristics. Each abnormality is discussed in an easy-to-follow three-column format. The first column lists the disease entities. The second column lists histologic criteria for diagnosis, with key features in boldface. The third column presents the differential diagnosis, helpful hints, and clinical information. Adjacent to the text are representative photomicrographs, accompanied where necessary by drawings to clarify cellular structures. New to this edition is a bound-in CD-ROM that contains over 2,000 full-color photomicrographs with more than 300 multiple-choice questions and answers for review and self-assessment.