In late 2016, officials at U.S. and Canadian diplomatic posts in Havana, Cuba, began reporting a cluster of symptoms, including nausea, severe headaches, and dizziness, that came to be known as “Havana Syndrome.” The illnesses prompted the departure of U.S. personnel from Havana in 2017, and subsequent cases have been reported among personnel assigned to the U.S. consulate in Guangzhou, China and elsewhere. In recent months, three reports related to the illnesses and the government's response have become public. A Center for Disease Control (CDC) report examined medical records and produced a case definition. A National Academies for Sciences, Engineering, and Medicine (NASEM) standing committee considered possible causes, including “directed, pulsed radio frequency (RF) energy, . . . chemical exposures, infectious diseases and psychological issues,” and concluded that the symptoms were consistent with RF effects. Additionally, a recently declassified Accountability Review Board (ARB) report criticized the Trump administration's response to the illnesses in Havana. Amid reports of increasing cases, including some occurring in the United States, the Biden administration is attempting to determine the cause of the illness and has committed to support affected personnel.