The incidence of cytomegalovirus (CMV) disease, one of the most prevalent opportunistic infections in HIV-infected persons in the early 1990s, has decreased by more than 80% since the introduction of highly active antiretroviral therapy (HAART). The rare cases of CMV disease still observed in Western countries occur mainly in profoundly immunosuppressed patients who have failed to respond to HAART. A new finding is the occasional occurrence of inflammatory retinitis in some patients on HAART with a history of healed retinitis. New tools for CMV detection have become available recently, including use of polymerase chain reaction (PCR) to detect CMV DNA from plasma. It has been possible to redefine, in the HAART period, patients at risk for CMV disease as those who have a low CD4 cell count as well as a blood marker of CMV blood dissemination (plasma CMV DNAaemia or high pp65 antigenaemia). Besides the classical therapeutic approach using ganciclovir (GCV), foscarnet and cidofovir, development of valganciclovir (VGCV), an orally administered prodrug of GCV, appears promising. There is evidence to suggest that it is as effective as intravenous GCV for the treatment of CMV retinitis, and it is currently being studied as a pre-emptive therapy in patients at high risk for CMV disease. Finally, patients with inactive CMV retinitis receiving HAART and with stable immune reconstitution may be able to discontinue maintenance therapy provided a regular ophthalmological and virological surveillance is maintained.