• The multiaxial system for evaluation is widely regarded as one of the most important contributions of DSM-III. The concept of multiaxial evaluation, that an individual is evaluated in terms of several different domains of information that are assumed to be of high clinical value, was introduced in the United States in the mid-1970s. Its value for clinical and research work was quickly recognized, and in the first year of the development of DSM-III, in 1976, a decision was made to incorporate such a system in the manual. This report reviews both the background of the development of the DSM-III multiaxial system and critiques that have been made of each of the axes since its publication in 1980. A companion report reviews empirical studies of the system and offers suggestions for its further development.