Genital herpes is the main cause of genital ulcers worldwide; the prevalence of herpes simplex virus (HSV) type 2 infections in the general population ranges from 10% to 60%. Most genital herpes is caused by HSV-2, although HSV-1 accounts for about half of new cases in developed countries. The risk of HIV acquisition is three times higher in people with HSV-2. Neonatal herpes is an uncommon but serious complication of genital herpes. Most genital HSV-2 infections are unrecognised and undiagnosed; infected individuals, even with mild symptoms, shed HSV, and can infect sexual partners. Since clinical diagnosis is neither sensitive nor specific, virological and type-specific serological tests should be used routinely. Oral antiviral drugs for HSV infections are safe and effective and can be used both to treat episodes and to prevent recurrences. Antiviral treatment of the infected partners and condom use reduce the risk of sexual transmission of HSV-2.