Oral and perioral herpes simplex virus (HSV) infections affect nearly 60% to 95% of human adults. The majority of HSV primary orofacial infections are asymptomatic. Primary herpetic gingivostomatitis (PHGS) is the most common orofacial manifestation of HSV primary infection. It is characterized by oral and/or perioral vesiculoulcerative lesions and acute generalized marginal gingivitis. Recurrent lesions are common on the lips (recurrent herpes labialis) and less common intraorally (recurrent intraoral herpes). In immunosuppressed patients HSV lesions may be large and persistent, diagnosis is often delayed because of the atypical presentation. Complications during HSV infection are rare. Occasionaly dehydration, viremia and visceral dissemination of the virus may occur, primarily in children and immunosuppressed patients. The diagnosis of both primary and recurrent herpetic infections is usually established by clinical presentation of lesions and specific laboratory testing is rarely indicated. Most of HSV infections are self-limiting and lesions heal in less than 2 weeks. The primary treatment for PHGS is supportive. Systemic antiviral drugs (aciclovir, valaciclovir and famciclovir) are used only if treatment is initiated within 72 hours of the outbreak of lesions in the oral cavity. Standard topical therapy for herpes labialis is aciklovir 5% cream and penciclovir 1% cream. Intraoral herpes treatment is symptomatic. Systemic antiviral drugs may be effective in reducing the duration of symptoms of recurrent HSV infection or may be used for prophylaxis of recurrent HSV infections to reduce the frequency and severity of recurrent attack.