The mutual interaction between hepatitis C virus (HCV) and human immunodeficiency virus (HIV) has clinical consequences and makes the management of coinfected patients complex. This review provides an update on the current knowledge on HIV/HCV coinfection. It is estimated that 30% of HIV-infected persons are coinfected with HCV. Prevalence is in even higher in drug users and in those with hemophilia. All HIV-infected patients should be screened for HCV, since HCV-related liver disease is a major cause of morbidity and mortality among HIV-infected individuals. The increased rate of liver complications in HCV/HIV coinfected patients is due to several factors: the decrease in opportunistic infections among patients brought about by the use of highly active antiretroviral therapy (HAART), the rapid course of chronic hepatitis C in dually infected patients, and the significant hepatotoxicity of antiretroviral drugs. Antiretroviral therapy should start early in coinfected patients, given the deleterious effect of immune deficiency on hepatitis C progression. Similarly, coinfected patients should be considered as potential candidates for HCV therapy, given their fast progression to end-stage liver disease and their high risk of liver toxicity after beginning antiretroviral therapy. However, individuals with <200 CD4+ cells/mm3 should be deferred from treatment because of poorer response rate and the possibility of a further interferon-induced decline in CD4 count. The treatment of choice is a combination of pegylated interferon alpha and ribavirin. Sustained virological response is lower (40%) than it is in HCV-monoinfected (60%) persons as it is negatively affected by the HIV-related immune dysfunction, more advanced fibrosis stages, higher serum HCV ribonucleic acid titers, and treatment discontinuation due to more frequent side effects. In order to improve treatment responses, a more prolonged duration of therapy, higher doses of ribavirin, and an individualized management of side effects should be considered.  Given the improved results achieved with HAART, liver transplantation is currently being proposed for HIV/HCV-coinfected patients with end-stage liver disease.