This article describes the ways in which economic crisis and the U.S. embargo have affected Cuba's health care system during the past 15 years. With the demise of subsidized trade, the absence of aid from the former Soviet Union, and the progressive tightening of U.S. sanctions, Cuba's model health care system has become threatened by serious shortages of medical supplies. Several public health catastrophes have occurred, including an epidemic of blindness that was partially attributed to a dramatic decrease in access to nutrients; an outbreak of the Guillain-Barré syndrome caused by lack of chlorination chemicals; and an epidemic of lye ingestion in toddlers due to severe shortages of soap. The policy of mandatory quarantine for HIV-infected Cubans has evolved into a less rigid system. Although the prevalence of HIV infection in Cuba is low compared with that in the United States and other Caribbean nations, it is threatened by prostitution, which has increased along with tourism. In general, economic sanctions may have an unintended but profound effect on the health and nutrition of vulnerable populations.