The expert advisory group for this health technology assessment (HTA) was established to assess the clinical and economic impact of a pre-exposure prophylaxis (PrEP) programme for populations at substantial risk of sexual acquisition of HIV. The public and/or patient (PPI) representatives were involved in supporting HIQA to fulfil its health technology assessment function. All expert advisory group members provided input into the process (for example, forming the terms of reference, drafting key considerations in the report, interpreting research findings) and they also provide peer review of the project report. The public and/or patient representatives were engaged from September 2018 to June 2019. The expert advisory group met twice during this period.