In this review, different techniques of total body irradiation are discussed with special attention to their advantages and disadvantages. The results of an EBMT questionnaire, which was sent out to the European TBI centres, are also presented. It turned out that there exists a great variety in techniques, total doses, and fractionation schedules used all over Europe. It was also clear that the documentation concerning dosimetry and the time factor in TBI still has some deficiencies. Therefore, a proposal is now made for reporting the technical and dosimetric aspects used in total body irradiation in an unambiguous manner.