INTRODUCTION: Lesotho has the third highest HIV prevalence in the world (an adult prevalence of 23.2%). Despite a lack of resources for health, the country has implemented state-of-the-art antiretroviral treatment guidelines, including early initiation of treatment (<350 cells/mm3), tenofovir in first line, and nurse-initiated and managed HIV care, including antiretroviral therapy (ART), at primary health care level. PROGRAMME APPROACH: We describe two-year outcomes of a decentralized HIV/AIDS care programme run by Doctors Without Borders/Médecins Sans Frontières, the Ministry of Health and Social Welfare, and the Christian Health Association of Lesotho in Scott catchment area, a rural health zone covering 14 clinics and one district hospital. Outcome data are described through a retrospective cohort analysis of adults and children initiated on ART between 2006 and 2008. DISCUSSION AND EVALUATION: Overall, 13,243 people have been enrolled in HIV care (5% children), and 5376 initiated on ART (6.5% children), 80% at primary care level. Between 2006 and 2008, annual enrolment more than doubled for adults and children, with no major external increase in human resources. The proportion of adults arriving sick (CD4 <50 cells/mm3) decreased from 22.2% in 2006 to 11.9% in 2008. Twelve-month outcomes are satisfactory in terms of mortality (11% for adults; 9% for children) and loss to follow up (8.8%). At 12 months, 80% of adults and 89% of children were alive and in care, meaning they were still taking their treatment; at 24 months, 77% of adults remained in care. CONCLUSION: Despite major resource constraints, Lesotho is comparing favourably with its better resourced neighbour, using the latest international ART recommendations. The successful two-year outcomes are further evidence that HIV/AIDS care and treatment can be provided effectively at the primary care level. The programme highlights how improving HIV care strengthened the primary health care system, and validates several critical areas for task shifting that are being considered by other countries in the region, including nurse-driven ART for adults and children, and lay counsellor-supported testing and counselling, adherence and case management.