Through a comprehensive review of the literature on sexual assault, the authors propose to clarify the different stages of the exam and help the practitioner to the forensic interpretation of lesions. The authors describe the basic principles that make consensus in how to interview victims in order to increase the reliability of the information collected. The various medical data that must be collected allowing to guide diagnosis (urogenital symptoms, sexual behaviour disorder) or facilitate the interpretation of lesions (age of puberty, use of tampons...) are specified as well as the different positions of examination and their association to other complementary techniques (Foley catheter, colposcopy, toluidine blue). The authors present a simple decision tree that can help the practitioner to interpret the laceration of the hymen. They detail the description and forensic interpretation of all genital lesions that may be encountered as a result of sexual assault, and the pitfalls to avoid. Finally, two main problems in the interpretation of lesions are described, the absence of injury after penetration and the accidental genital lesions.