This special issue of the South African Medical Journal is devouted to the South African Stress and Health (SASH) survey. This study is significant for a number of reasons. Firstly, SASH is the first nationally representative epidemiological survey of common mental disorders in South Africa, or indeed in Africa. Secondly, SASH used a similar methodology to other surveys in the World Mental Health Survey (WMHS), allowing comparison of local findings with those in a range of high-, low- and middle-income countries. Thirdly, SASH had a particular focus on psychological trauma, and so provides a unique perspective on this potentially important risk factor for mental disorder.