In the first part of the book Dr. Hirsch discusses 'the multiple factors producing individual juvenile delinquents'. He assumes these to be heredity and environment, accidental causation and genius. He has a special chapter on the incidence of enuresis in the cases that came under his observation. The second half of the book consists of case records, with a short chapter on suggestions as to methods of dealing with the problem of juvenile crime.

Impressive features of the book are the detailed and careful compilation of factual and psychological data at the author's disposal, and the breadth of the author's approach to his subject. He makes a determined effort to define and clarify such working concepts as heredity and environment and he offers eight laws regarding the interrelations between these two factors; yet his discussion remains more or less general and he does not establish definite and tangible criteria as to the application of these laws in specific cases. Most tangible are the causes grouped under accidental