The aim of the paper is to examine the relationship between blood pressure (BP) and renal disease with an overview of observational and experimental investigations, with the emphasis on studies that provide data obtained in unselected population samples. We have found an increasing body of evidence from cross-sectional, case-control, prospective, and experimental studies that indicate BP is an important, independent predictor of both increased relative and attributable risk of renal insufficiency and end-stage renal disease. The relationship between BP and subsequent renal disease appears to be positive and continuous throughout the entire range of BP. Furthermore, the data indicate that elevations in systolic BP (SBP) are stronger predictors of risk compared to corresponding increases in diastolic BP (DBP). Clinical trials experience suggests that reduction in BP decreases the risk of subsequent renal disease. Ongoing trials should help to clarify issues related to choice of antihypertensive therapy and optimal goals for reduction of BP in order to prevent renal disease.