External genital warts (EGWs) are sexually transmitted benign epidermal growths caused by the human papillomavirus (HPV), on the anogenital areas of both females and males. About 50% to 60% of sexually active women aged 18 to 49 years have been exposed to HPV infection, but only 10% to 15% will have genital warts.We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for external genital warts? What are the effects of interventions to prevent transmission of external genital warts? We searched: Medline, Embase, The Cochrane Library, and other important databases up to December 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).We found 55 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.In this systematic review we present information relating to the effectiveness and safety of the following interventions: bi- and trichloroacetic acid; condoms; cryotherapy; electrosurgery; imiquimod; intralesional, topical, or systemic interferons; laser surgery; podophyllin; podophyllotoxin; surgical excision; and vaccines.