High blood pressure affects 65 million Americans. Another 59 million Americans have prehypertension, which increases their chances of developing cardiovascular disease. People over 55 have a 90 percent chance of developing high blood pressure in their lifetime. High blood pressure is a major risk factor for 3 of the 10 leading causes of death in the United States: heart disease (#1), stroke (#3), and kidney disease (#9) (source: National Center for Health Statistics). As the United States population becomes older—and increasingly overweight and obese—high blood pressure will become an even bigger problem. Hypertension imposes an especially heavy burden on the health of African Americans. Hypertension can be prevented by lifestyle modification, including weight loss and salt reduction, but the achievement of these goals in primary care has been disappointing. At Johns Hopkins, GIM faculty are engaged in the investigation and treatment of hypertension across the full range of its natural history.