This article argues that Anna Freud’s diagnostic aim of assessing a child’s developmental status to obtain a picture of the child’s total personality remains central and relevant to contemporary child mental health. It introduces the work of a research group at the Anna Freud Centre which re-examined Anna Freud’s Provisional Diagnostic Profile (1965), in 2001 and again in 2016, to include contemporary developmental psychology and attachment research. The resulting 2016 revised Diagnostic Profile is published in this issue for the first time.