This satellite session will launch the JIAS supplement "Integrating services for HIV and related comorbidities: modelling to inform policy and practice." While people living with HIV (PLWH) are living longer due to antiretroviral treatment (ART), they are developing non-communicable diseases (NCDs) as they age. These NCD co-morbidities are not being diagnosed or treated in many low-and middle-income countries (LMICs). In countries with generalized HIV epidemics, a question asked is: What is the most cost effective way to implement integrated HIV/NCD care? In countries where the epidemic is concentrated within key populations, a question is: Can we integrate HIV and mental health or substance use services? To answer these questions data can be provided through mathematical modeling and surveys. This supplement highlights several examples of the use of mathematical modeling to provide data to make decisions on how to provide more comprehensive care to PLWH.