Education is the most important factor in behaviour change, especially in a situation as complex as the HIV epidemic. Ironically, in Taiwan, once the epidemic among IDUs was controlled, a hidden epidemic among homosexuals (including bisexuals) became apparent. The number of newly HIV-infected homosexuals increased steadily, from 472 (14%) in 2005 to 861 (49%) in 2008, as shown in Table 2 . In other words, approximately half of the newly reported infections occurred among homosexuals. This suggests the need to deliver appropriate messages to that group, using culturally sensitive and gender-sensitive approaches. Developing an appropriate non-formal educational approach to the MSM group might become the next challenge now that the high incidence among IDUs has been reduced.