Vaso-occlusive crises with bone and joint pain, ischemia, and infarction are common and major clinical manifestations of sickle cell anemia and its variants, sickle cell hemoglobin C disease, and sickle cell-thalassemia. Well known to the pediatrician and the pediatric hematologist, bone infarction is amply and reasonably well documented in most available general and subspecialty textbooks. The main purpose of Dr Bohrer's monograph, the most complete and refreshing treatise on the subject to date, is to illustrate, describe, and discuss acute and chronic bone ischemia in sickle cell anemia and heterozygous sickle cell states. Dr Bohrer has devoted his career to the study of ischemic osteonecrosis, osteomyelitis, and infarctive bone necrosis in sickle cell anemia. He had extensive experience in Ibadan, Nigeria, from 1967 through 1977 and has compiled a magnificent collection of roentgenograms. As he clearly cautions the reader, sickle cell anemia in Nigerian children is clinically dissimilar to the