The Caribbean subregion was one of the first areas to successfully integrate measles and rubella surveillance, and it can serve as an example to other subregions on how to achieve similar success. The integrated surveillance system, established through strong political commitment by Caribbean countries, is coordinated by the Caribbean Epidemiology Centre (CAREC). The system, which became operational in January 2000, is designed to detect and investigate patients with fever and rash illness, and also test a blood specimen from each case investigated. During over 9 years of operation, 3733 cases were reported and investigated. Laboratory tests identified 2 imported cases of measles, 27 cases of rubella, 309 cases of dengue, and 260 cases of human herpesvirus 6 (HHV-6) infection. The lessons learned from the success of this integrated system indicate that the following factors are critical: strong political commitment, strong technical oversight from all levels within the health-care system, the use of proven tools or systems and technology for data collection and analysis, integration with other surveillance activities, continuing training, and continuing review and evaluation.