Lymphogranuloma venerum (LGV), an ulcerative sexually transmitted infection caused by the L serovars of Chlamydia trachomatis, has gained recent attention as a cause of hemorrhagic proctitis among men who have sex with men in North America, the United Kingdom, and Europe. It has been a rare diagnosis, and likely has not been included in the routine differential diagnosis for proctocolitis. The lack of a specific diagnostic test has complicated LGV case ascertainment. In the absence of laboratory confirmation of L serovars, physicians are advised to treat possible cases presumptively for LGV and provide medical management of sexual partners. The appearance of an ulcerative infection in sexual networks with high rates of HIV coinfection may forewarn of increased HIV transmission; interruption of disease transmission remains a priority for medical providers and the public health community.