Although syphilis has been a reportable disease since the 1940s, it was rarely reported by physicians. An amendment to the Public Health Code lifted the requirement to report sexually transmitted diseases in July 2000. During the 1990s, syphilis was a very rare disease in sexually transmitted disease clinics (STD clinics). In late November 2000, a resurgence of syphilis led to the establishment of a surveillance system. The objectives of this system are to monitor, in participating centers, the annual trend in the number of adults with syphilis and to describe their clinical, biological, and behavioral characteristics. This article presents the surveillance data for 2000–2002.