Adolescents who acquire HIV infection during adolescence (ie., by horizontal rather than vertical transmission) follow a similar clinical course to that of adults. Antiretroviral therapy should be commenced as soon as practical provided the young person is willing to adhere to therapy.^[12],[13] Initial ART regimens are likely to be focused on simplification, given that the young person will not have had prior exposure to antiretroviral drugs and there are fewer concerns around antiretroviral drug resistance and intolerance. Psychosocial support remains an important component of care as the young person comes to terms with their diagnosis; navigates disclosure (if they so choose) to family, peers and sexual partners; and encounters potential issues of self- and social-stigma. Particular attention should be paid to at-risk behaviours (e.g., sexual activity and substance use) through which the young person may have acquired HIV infection and may transmit it to others.