U.S. and international efforts to control carabapenem-resistant Enterobacteriaceae (CRE) are critical to protect public health. Clinicians caring for patients infected with such organisms have few, if any, therapeutic options available. CRE containing New Delhi metallo-beta-lactamase (NDM), first reported in a patient who had been hospitalized in New Delhi, India, in 2007, are of particular concern because these enzymes usually are encoded on plasmids that harbor multiple resistance determinants and are transmitted easily to other Enterobacteriaceae and other genera of bacteria. A urine specimen collected on March 4, 2012, from a patient who recently had been hospitalized in Viet Nam, but who was receiving care at a hospital in Rhode Island, was found to have a Klebsiella pneumoniae isolate containing NDM. The isolate was susceptible only to tigecycline, colistin, and polymyxin B. Point-prevalence surveys of epidemiologically linked patients revealed transmission to a second patient on the hematology/oncology unit. These two cases bring to 13 the number of cases of NDM reported in the United States. After contact precautions were reinforced and environmental cleaning was implemented, no further cases were identified. Similarly aggressive infection control efforts can limit the spread of NDM in acute-care medical facilities.