In the past decade health care expenses have increased by 50% in Italy, a country whose population mostly consists of people aged over 50 years old, the main users of health care services. Pharmaceutical expenditure is the main issue: monoclonal antibodies, biological immunosuppressants, antitumorals and antiretrovirals are the most expensive drugs. The cost of HIV/AIDS has remained constant during the last four years. Despite the increase in pharmaceutical costs, which made the infection chronic, hospitalization costs have been reduced. With sustainable economic development as a chiefly long-term target, a clinical governance system is nonetheless needed which also takes account of the adherence to antiretroviral therapy: thus poor adherence leads to a reduction in efficacy and at the same time an increase in welfare and community costs. Recently in SSvD "Prevention and cure of HIV infection and related syndromes" of "Maggiore della Carità" University Hospital, Novara, adherence to antiretroviral therapy in 100 consecutive patients was evaluated. The results show that patients with high adherence to the treatment prescribed have a less expensive drug combination. Moreover, with better infection control and a higher immune recovery, they have less impact on social and health care costs.