Due to the rapid expansion of first-line antiretroviral therapy in resource-limited settings (RLS), increasing numbers of people are living with HIV for prolonged periods of time. Treatment programs must now decide how to balance monitoring costs necessary to maximize health benefits for those already on treatment with the continued demand to initiate more patients on first-line treatment. We review currently available evidence related to monitoring strategies in RLS and discuss their implications on timing of switching to second-line treatment, development of HIV resistance, and clinical outcome.