.... Design/methodology/approach The clinical use of the ABC and similar measures is discussed and contrasted with function-based approaches to assessment. Findings While classification tools such as the ABC have played an important role in developing the understanding of challenging behaviour...

...Alan Leyin This article explores the nature of the classifications of learning disabilities as promulgated in the diagnostic manuals. By leaving aside all doubts and controversies that surround the concept and measurement of intellectual functioning, weaknesses are exposed from within those manuals...