Originally published in 1985, this book was an attempt at a comprehensive review of the psychology of action in various areas of psychology. It is also an attempt to bridge two languages and traditions in psychology: German and Anglo-American. Although Anglo-American psychology had had an enormous influence on German psychology, the influence had not gone the other way around - at least not in recent years. Therefore, this book attempts to get the two traditions to speak with each other. The main article, from one language area, and the following discussion, from the other language area, together result in an extensive treatment of an action-theoretic approach in the respective psychological area; thus, both the main article and "discussion" should be read together.