This paper explores HIV patients' adherence to antiretroviral treatment (ART) in resource-limited contexts in Uganda and Ethiopia, where ART is provided free of charge. Qualitative semi-structured interviews were conducted with 79 patients, 17 peer counselors, and 22 providers in ART facilities in urban and rural areas of Ethiopia and Uganda. Interviewees voiced their experiences of, and views on ART adherence both from an individual and a system level perspective. Two main themes emerged from the content analysis: "Patients' competing costs and systems' resource constraints" and "Patients' trust in ART and quality of the patient-provider encounters." The first theme refers to how patients' adherence was challenged by difficulties in supporting themselves and their families, paying for transportation, for drug refill and follow-up as well as paying for registration fees, opportunistic infection treatment, and expensive referrals to other hospitals. The second theme describes factors that influenced patients' capacity to adhere: personal responsibility in treatment, trust in the effects of antiretroviral drugs, and trust in the quality of counseling. To grant patients a fair choice to successfully adhere to ART, transport costs to ART facilities need to be reduced. This implies providing patients with drugs for longer periods of time and arranging for better laboratory services, thus not necessitating frequent revisits. Services ought to be brought closer to patients and peripheral, community-based healthworkers used for drug distribution. There is a need for training providers and peer counselors, in communication skills and adherence counseling.