A comprehensive study of ARV adherence and possible factors facilitating or constraining adherence to ART in Tanzania has not yet been attempted. Elsewhere, studies in other countries have described a range of factors affecting ARV treatment adherence at various levels, including individual, community and health facility levels (Weiser at al., 2003; Horne 1998; Eldred et al., 1998). These factors can be broadly grouped into three categories: structural factors, disease and treatment factors, and social and economic factors. The structural factors include inadequate support services, limited accessibility of treatment, long distances to the health facility, lengthy waiting times, and the attitudes and quality of care of the health care staff. The disease and treatment factors include the seriousness of the disease, adverse drug reactions, and side-effects. The socioeconomic factors include poor patient knowledge and information, illiteracy, lack of social support, poverty, stigma, misconceptions about HIV and AIDS, and communication barriers between patients and doctors/care-givers (see Figure 1 below).