Vaginitis is a general term for inflammation of the vagina with symptoms such as vulvovaginal itching, burning, irritation, dyspareunia, odor, or abnormal vaginal discharge. It is a common condition that results in 5 million to 10 million office visits annually. The leading infectious causes of vaginitis are bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis. Noninfectious causes include atrophic, irritant, and inflammatory vaginitis. Bacterial vaginosis usually presents with a thin, homogenous vaginal discharge and a fishy odor. Vulvovaginal candidiasis often manifests with a white, thick, curd-like discharge, pruritus, and vulvar erythema. Trichomoniasis usually presents with a green or yellow frothy discharge, and speculum examination may reveal cervical erythema with petechiae. Noninfectious vaginitis can present with clear or purulent discharge and can be pruritic depending on the etiology. Bacterial vaginosis can be diagnosed using Amsel criteria, Gram stain, or a nucleic acid amplification test (NAAT). Vulvovaginal candidiasis can be diagnosed by visualization of yeast hyphae or budding yeast on microscopy, vaginal fungal culture, polymerase chain reaction testing, or NAAT. Trichomoniasis can be diagnosed with visualization of motile, flagellated protozoa on saline microscopy, NAAT, or DNA probe test. Bacterial vaginosis is treated with oral or intravaginal metronidazole or intravaginal clindamycin. Vulvovaginal candidiasis is managed with topical or oral antifungals. Trichomoniasis is treated with oral metronidazole or tinidazole. When treating trichomoniasis, testing for reinfection, as well as other sexually transmitted infections, is recommended. Treatments for noninfectious vaginitis include vaginal lubricants and moisturizers, topical hormones, and topical steroids, depending on the cause.