The symposium here reported took place in Istanbul under the auspices of a group of 50 international voluntary associations of specialists belonging to all the medical disciplines. The 26 papers, by different authors, with discussions, cover genetic and physical factors in the heterogeneity of hemoglobins, their identification and interpretation, clinical aspects, the hemoglobins in children and in different diseases, and the geographical distribution of different hemoglobins. Two papers deal with paper electrophoresis and serologic differentiation. An extensive bibliography is given, as well as a helpful index. The material is highly technical and presupposes a thorough knowledge of genetics, with an understanding of the exact meaning and true significance of such words as "genes," "alleles," "dimerization," "phanerosis," and "a propositus for the sibship." One should also have a working knowledge of electrophoretic, chromatographic, and saltingout techniques to understand the many figures in the text. The book contains a tremendous amount of