Purpose of reviewAlthough the incidence of Kaposi's sarcoma in established market economies has fallen since the introduction of highly active antiretroviral therapy, it remains the most common tumour in individuals with HIV infection. Kaposi's sarcoma-associated herpesvirus is the aetiological agent of Kaposi's sarcoma and its role in the subversion of cellular machinery provides an understanding of the fundamental mechanisms involved in immunobiology and carcinogenesis. The focus of this review will be to discuss articles published from August 2001 to August 2002 that provide advances in our knowledge of this process, and also to review new data concerning the transmission and identification of Kaposi's sarcoma-associated herpesvirus infection in different populations.Recent findingsWe have an improved understanding of the epidemiologies of classic, endemic, post-transplant and AIDS-associated Kaposi's sarcoma. The role of specific genes in tumorigenesis has been further defined, with particular reference to the switch from latent to lytic infection and the involvement of cytokines and angiogenic factors.SummaryKaposi's sarcoma-associated herpesvirus is widespread in immunosuppressed individuals and is associated with significant morbidity and mortality. The study of Kaposi's sarcoma and Kaposi's sarcoma-associated herpesvirus represents an important model of the interplay between the immune system and cancer, and may lead to the development of clinically useful therapies including vaccines.