SYSTEMATIC investigation of the growth of children with congenital intracardiac defects has been carried on at the Heart Research Institute of the Pacific Medical Center since 1962. The purpose of these studies has been to define the characteristic growth patterns of such children as a background for interpreting effects of surgery, the impact of selected physiologic variables, and any differences within the group according to sex, age, and diagnostic category. The present report deals with size as related to the latter three factors in 317 children. Data Collection Anthropometric Studies.—These are based on standard techniques involving five direct body measures; five ratios derived from them; skeletal age assessments by the standards of Greulich and Pyle1 from roentgenograms of the left hand and wrist; and sets of four photographs at each examination. The methods are essentially those described by Bayer and Bayley.2 Studies have been made before surgery,