The Uganda Pediatric and Adolescent HIV Cohort on Antiretroviral Therapy (UP ART), is an observational cohort study which aims to establish a nationally representative observational pediatric and adolescent HIV cohort on ART in Uganda. The cohort aims to generate high quality data on children and adolescents in routine HIV care across the country, to address key public health questions such as the uptake and impact of the roll out of new treatments and guidance on HIV care.