Perineal trauma is a common consequence of vaginal childbirth. This may be spontaneous or an iatrogenic event following an episiotomy, or a combination of the two. One UK study states that up to 85% of women experience some form of perineal damage during labour. Many of these are minor lacerations, but up to 70% may require suturing. Obstetric anal sphincter injuries (OASIS) are severe perineal lacerations involving part or all of the anal sphincter complex. Improved knowledge and education in the identification and management of OASIS are essential in view of the substantial acute and chronic morbidity associated with such trauma.