Behavioural change programmes specifically those promoting faithfulness, partner reduction and consistent right condom use contributed to the early declines in HIV incidence and prevalence in Uganda. To guard against treatment optimism and continued risky sexual practices which might result from improved health status, ART clients are also subjected to intensive behavioural change intervention campaigns in Uganda. However, comprehensive evaluation of behavioural change interventions /programmes and the impact of ART on sexual behaviour in Uganda is scarce and limited to only six months duration on ART. This thesis investigated ART clients’ knowledge about HIV/AIDS and ART, patterns of VCT services use prior to ART initiation, sexual practices before and after ART initiation. The extent to which ART clients adapt to HIV/AIDS preventive measures and the appropriateness of the health education model were also investigated. A cross sectional study was conducted between June–September 2008 among Villa-Maria hospital clients in Masaka district Uganda. A purposive convenient sampling technique was applied to select a total of 48 participants. Data was collected using interviewer administered questionnaire, in-depth interviews and focus group discussions. A total of 48 questionnaires were administered, 16 in-depth interviews and 4 focus group discussions with 32 participants were conducted.