Health care providers who evaluate persons who have or are at risk for sexually transmitted diseases (STDs) should be aware of current national guidelines for STD treatment and should provide assessment and treatment according to these recommendations. The Centers for Disease Control and Prevention STD Treatment Guidelines were developed by using an evidence-based approach incorporating available scientific evidence, specialist knowledge, and consultation with professional organizations and other agencies with diverse perspectives on STD treatment. The guidelines provide recommendations about new antimicrobial agents for the treatment of primary and recurrent genital herpes, a novel patient-applied therapy for genital warts, additional parenteral alternative regimens for the treatment of pelvic inflammatory disease, oral therapy for vaginal candidiasis, and alternative regimens for treatment of chlamydia in pregnancy. Expanded sections in the guidelines also address the management of urethritis, recognition of the acute retroviral syndrome, and the emergence of quinolone-resistant Neisseria gonorrhoeae. Prevention of sexually transmitted hepatitis A and hepatitis B through the use of preexposure vaccinations is discussed.