AIDS has been responsible for concentrated research and health care efforts. These initiatives have led to major advances in therapeutic possibilities, which have been accompanied by new demands on HIV-positive people undergoing treatment, such as the need for high levels of adherence, in the order of 95 per cent of the prescribed doses, in order for satisfactory results to be obtained. The aim of this study was to describe and evaluate the effects of group cognitive-behavioural intervention strategies on the adherence behaviour to antiretroviral treatment of HIV-positive people with adherence difficulties.