Discusses whether national context has influence on the experience and use of highly active anti-retroviral therapy for people living with HIV/AIDS. Information on a research of the International Collaboration on HIV Optimism on the comparison of gay men in terms of their levels of optimism about the effects of highly active anti-retroviral therapy; Statements used in the questionnaires to capture the degree of susceptibility and severity of HIV perceived in the context of treatments; Optimism scores of the population studied; Discussion on the role of informal carers in AIDS social care.