To reach such an understanding it is not necessary that the business man enter into the depths of all those dark questions over which the scientific psychologists are wrangling. The scholarly volumes on psychology written for specialists certainly contain much which would be of no importance for the practical man. It is the aim of this volume on business psychology to bring together those results of modern psychological thinking which are sig~ nificant for the work of the business man. Yet business psychology too is, after all, psychology, that is, a science which needs serious and penetrating study. N 0 one ought to believe that a science can be mastered in any other way than by serious study.