The question of patient confidentiality is becoming more important with the ever-changing litigious world of obstetrics and gynaecology. This article aims to highlight areas met in clinical practice that might legally justify a breach of patient confidentiality, and to give the legal authority that supports the breach. It will focus on patients with transmissible diseases such as HIV/AIDS, domestic and other physical violence, assisted conception, termination of pregnancy and sterilization, and contraception for the under 16s.