Operative syn-drome is defined as a psychiatric complication, which may develop in patients undergoing surgery. Ten of these syndromes are described and examples of cases are cited. These range from negativistic behavior through preoperative anxiety, postoperative psychosis to delayed recovery. Emphasis is placed on a method of rapid evaluation of the most pressing psychiatric problems, the explicit psychodynamic formulation of the problems, proposing a practical program of management, with stress on the importance of the active participation in the management by the psychiatrist. The program of management and the intervention by the psychiatrist are based on psychodynamic principles, but depend more on action and interplay than on interpretation. The method and theory is described in more detail in the 2d part of the paper.