Abstract: PART IIn the past the chief contributions to the better under- standing of congenital heart disease have been based on necropsy studies, particularly those by Peacock (1866), Keith, (1909), and Maud Abbott (1928).More recently, Brown (1939) and Helen Taussig (1947) have presented us with important monographs from a more practical angle, but even these have depended on the correlation of clinical and post-mortem findings.In some respects all these works have necessarily been influenced by the selected nature of the material, and have tended to create a number of false impressions.For example, of Abbott's 1,000 cases there were 37 with three-chambered hearts, 81 with partial or complete transposition of the great vessels, 40 with pul- monary atresia, 21 with persistent truncus, and 16 with tricuspid atresia (total 195); against 33 with atrial septal defect (A.S.D.), 55 with uncomplicated ventricular septal defects (V.S.D.), 105 with uncomplicated patent ductus, 9 with simple pulmonary stenosis, and about 71 with Fallot's tetralogy (total 273), giving a ratio of the rare to the com- mon types of 2:3.Again, in 1947 Helen Taussig stated that she hadnever had an opportunity of studying a single case of pure pulmonary stenosis.The suggestion that V.S.D. accounts for 35-40% of all congenital hearts seen in school-children (Perry, 1931 ; Muir and Brown, 1934) is also unacceptable.In recent years, modern techniques have made it pos- sible to prove the precise nature and physiological effects of 90% of all congenital cardiac anomalies during life.In the light of this rapidly acquired knowledge of dynamic processes, many physical signs have acquired a new significance and their proper interpretation has so greatly im- proved bedside diagnosis that the special investigations responsible for their discovery have already become super- fluous in many cases.The time is ripe, therefore, for a Teview of the whole subject of congenital heart disease from a more functional standpoint, to present a fresh account of these physical signs, to offer a more practical and physio- logical classification of the common or well-recognized anomalies, and incidentally to give a truer picture of their 'clinical incidence.By implication, stillborn infants and those dying shortly after birth have been excluded from the study.