Two longitudinal surveys were carried out in 1996 and 1999 aimed at describing the situations of AIDS-related discrimination in the workplace and evaluating the effectiveness of some social interventions against discrimination towards HIV-positive employees. Two hundred and ninety-nine and 212 companies completed a questionnaire in 1996 and 1999, respectively. The results are mixed. Although most of the sampled companies had no HIV/AIDS-related policy, their awareness of related legislation increased over the three-year period. Over the three-year study period, more companies indicated they would disclose information of their HIV-positive employees if known to the company; however, fewer companies indicated they would dismiss an employee because of his or her HIV-positive status. Only a few companies indicated that they would provide counselling and support to an HIV-positive employee.