Two patients with frontal lesions underwent re-education of the mental processes. The material used was the PM 38 test, WAIS cubes and visuo-spatial problems. The method used was based on Luria's re-education technique supplemented by a process of phasing out the controlling aids and cutting out facts for analysis. Results obtained before and after re-education in responses are described and compared. The problem of reansferring the skill acquired to other activities is discussed. The authors found that skills developed in the re-education situation to cope with a given task are not spontaneously utilised by the patient when he is again placed in a similar situation, but that a simple verbal cue from the tester is sufficient to cause this skill to be transferred. Finally, when faced with a new situation, the patient does not work out how to solve the problem, but he accepts more readily what is suggested to him by the tester.