OBJECTIVES: To (a) determine early treatment outcomes and (b) assess safety in children treated with adult fixed-dose combination (FDC) antiretroviral tablets. SETTING: Sixteen Medecins Sans Frontieres (MSF) HIV programs in eight countries in resource-limited settings (RLS). METHODS: Analysis of routine program data gathered June 2001 to March 2005. RESULTS: A total of 1184 children [median age, 7 years; inter-quartile range (IQR), 4.6-9.3] were treated with antiretroviral therapy (ART) of whom 616(52%) were male. At ART initiation, Centres for Disease Control stages N, A, B and C were 9, 14, 38 and 39%, respectively. Children were followed up for a median period of 6 months (IQR, 2-12 months). At 12 months the median CD4 percentage gain in children aged 18-59 months was 15% (IQR, 6-18%), and the percentage with CD4 gain < 15% was reduced from 85% at baseline to 11%. In those aged 60-156 months, median CD4 cell count gain was 275 cells/microl (IQR, 84-518 cells/microl), and the percentage with CD4 < 200 cells/mul reduced from 51% at baseline to 11%. Treatment outcomes included; 1012 (85%) alive and on ART, 36 (3%) deaths, 15 (1%) stopped ART, 89 (8%) lost to follow-up, and 31 (3%) with unknown outcomes. Overall probability of survival at 12 months was 0.87 (0.84-0.89). Side effects caused a change to alternative antiretroviral drugs in 26 (2%) but no deaths. CONCLUSIONS: Very satisfactory early outcomes can be achieved in children in RLS using generic adult FDC antiretroviral tablets. These findings strongly favour their use as an "interim solution" for scaling-up ART in children; however, more appropriate pediatric antiretroviral drugs remain urgently needed.