CAB-LA should be delivered as an additional choice alongside other PrEP options, including oral PrEP and the DVR, as part of a comprehensive HIV prevention approach. To date, provision of CAB-LA has largely been limited to trial settings, certain geographies and specific populations. This guideline outlines operational research needed to address research and implementation gaps, and to inform decisions on how to approach the implementation and scale-up of CAB-LA successfully. The GDG stressed that operational research – and implementation of services itself – must involve the full participation of interested communities from inception to implementation. As countries plan the introduction of CAB-LA, considerations should include optimal HIV testing strategies for initiation and continuation; service delivery models including differentiated service delivery to maximize accessibility and acceptability and to integrate CAB-LA as an additional choice in comprehensive services; and activities to create awareness and demand as well as training and support of providers. Operational research is needed to evaluate CAB-LA provision for key populations, particularly sex workers, people who use drugs, trans and gender-diverse people, as well as adolescents. As CAB-LA is a new product, research is also needed across a range of priority areas including optimal testing strategies and impacts on drug resistance, safety in pregnancy and breastfeeding, service delivery models and population-level impacts and cost-effectiveness, to support inclusion of CAB-LA as part of differentiated service delivery for HIV prevention.