The strategy for monitoring HIV/AIDS in China has evolved with the epidemic. The national HIV/AIDS surveillance system was established in 1985 and sentinel surveillance started in 1995. Initially, 42 sentinel sites were established to monitor the epidemic among certain high-risk groups, including drug users, female sex workers, STD clinic attendees and long-distance truck drivers in epidemic areas. In the last decade the programme has been considerably expanded. Target groups now also include pregnant women, men who have sex with men (MSM), clients of female sex workers and tuberculosis (TB) patients. By the end of 2006, 393 national and 370 provincial sites report to the National Centre for AIDS/Sexually transmitted disease Control and Prevention. In 2004, a nationwide HIV testing campaign was launched among certain high risk groups, including former plasma donors and injecting drug users. Routine testing in health care settings and detention centres was introduced in 2005. Behavioural surveillance began in 2004 and there were already 159 sites in 27 provinces by the end of 2006. In addition a number of epidemiological surveys have been undertaken among various groups to augment surveillance data. The combination of these comprehensive strategies is used to monitor the HIV/AIDS epidemic and guide policy decision-making. The Chinese experience illustrates how surveillance systems need to be dynamic in order to monitor trends in HIV over time.