Barbara Burmen has an interest in implementation science i.e. using routinely collected information (or research data) to support evidence-informed clinical, policy and programmatic decision making. With an increase in coverage of HIV testing and use of antiretroviral regimens for HIV prevention and treatment in pregnancy, there are improvements in maternal health and survival and decreases seen in HIV transmission from mother to child. Subsequently, the proportion of children exposed to HIV who are themselves uninfected is increasing. There is a need to assess whether these interventions are sufficient to ensure comparable health outcomes between children who are HIV exposed and uninfected (CHEU) and children who are HIV unexposed and uninfected (CHUU). As a preliminary step, Burmen is working (with a project team drawn from the Collaborative Initiative for Paediatric HIV Education and Research, CIPHER, Paediatric HIV Cohort Investigator Consultation) to develop standardised exposure and outcome definitions of HIV and ARV exposures for CHEU & CHUU.