An analysis is provided of a recent Australian epidemic of an upper limb regional pain syndrome known as 'repetition strain injury' (RSI). 'RSI' was originally attributed to occupational over-use of the upper limb and biomechanical and ergonomic solutions were sought. More sceptical commentators argued that 'RSI' was an epidemic form of hysteria. More recently, a consensus has emerged that the epidemic is attributable to a combination of factors: a change in the perception of endemic symptoms of upper limb pain; the iatrogenic effects of the term 'RSI' and the methods used to manage it; and complications of the medico-legal process in which many sufferers became entangled.