Praxiology: An introduction to the Sciences of Efficient Action deals with the general theory of achieving efficient actions. The concept of a praxiology and the technique of a praxiologist toward finding the most efficient way of achieving things are the concerns in this book. Praxiology is discussed as being the codification for practical behavior. The notions of praxiology is clarified and the tasks of registering and ordering what are already known and existing concepts of efficient work are gathered and presented. This book also shows the concepts of the simple act of the agent, the free impulse, material, tool, and product involved in any kind of external work that is undertaken. An analysis following instruments as the source of power in themselves is considered, because these instruments can exert pressure on the external work being done. This text then discusses action as a compound act or a collective act. Then, the author expounds that among other possibilities, there is only a fine possibility that an action can be done. Taken into consideration are the praxiological values, the economization, preparation, and instrumentalization of actions. The principles of co-operation are discussed, compared to struggling or negative cooperation, as leading to improved accomplishment and efficiency of work. The author adds that praxiology can be applied mentally as well, but he considers this as a special case. Psychologists, psychiatrists, work process engineers, and behavioral scientists will find this book illuminating and educational.