Sexually transmitted diseases are notable for their fastidious requirements for transmission and growth and psychosocial morbidity. The combination of subtle or absent symptoms and stigma preventing the seeking of health care leaves many infections undiagnosed. Sexually transmitted diseases frequently affect the mucous membranes producing characteristic and potentially diagnostic lesions on the oral mucosa. The classic route of transmission and the corresponding clinical presentation of several of the sexually transmitted viruses, including herpes virus types I and II, Epstein Barr virus, Cytomegalovirus, Human Papilloma virus, Molluscum Contagiosum, as well as the Human Immunodeficiency Virus along with bacterial infections such as syphilis, gonorrhea, and the fungus candida are reviewed in this text book under the umbrella of STDs with potential oral involvement encountered in the sexually active patient.