Favorable trends in risk factors have contributed to the decline in stroke mortality. Risk factors for stroke include older age, male sex, black race, low socioeconomic status, heart disease, hypertension, diabetes mellitus, certain medications, cigarette smoking, alcohol, and diet. Improvements in economic and living conditions may have contributed to the decline in stroke mortality. However, increasing longevity, growth in population size, and increased survival with coronary heart and other cardiovascular diseases are likely to increase the numbers of strokes in the future. Effective treatment of hypertension is credited with accelerating the decline in stroke death rates since the 1970s. Reductions in cigarette smoking since the 1960s and in alcohol consumption in the 1980s may have contributed to the more recent decline in stroke mortality, especially among men. Dietary changes possibly related to improvements in stroke rates include lower saturated fat and salt intake. Primary prevention through reductions in highly prevalent risk factors is an important strategy for continuing the decline in stroke mortality.