PURPOSE OF REVIEW: HIV-infected individuals have a greatly increased risk of developing malignancies, even when HIV infection is successfully controlled with antiretrovirals. Non-Hodgkin's lymphoma is considered an AIDS-defining entity, and this disease is currently the most common type of cancer in HIV-infected individuals in the USA and Europe. Here, we describe the different types of lymphomas occurring in individuals with AIDS, and the most relevant pathologic features helpful for histologic and immunohistochemical diagnosis. RECENT FINDINGS: The incidence of some AIDS-related lymphoma subtypes has changed since the introduction of combined antiretroviral therapy, and some of the diagnostic methodologies have evolved. New biomarkers of disease have been identified, which may be useful for diagnosis. SUMMARY: Better pathological classification strategies and deeper molecular understanding of the different lymphoma subtypes that occur in people with AIDS will begin to allow the transition to more precise diagnosis and targeted treatments.