With the recent rapid increase in scientific understanding of the human genome it is becoming possible to identify the extent to which genetic variations influence drug response. The emergence of pharmacogenetics heralds a new era in which drug therapies will be selected on the basis of differences in individuals' genotypes, enhancing drug safety and efficacy. The major focus of this review is pharmacogenetics of antihypertensive drugs. Genetics can influence the pharmacokinetics and pharmacodynamics of such drugs at different levels. The presently available applications of genetic concepts to some drugs commonly used in the treatment of hypertension (ACE-inhibitors, diuretics, beta-blockers...) will be summarized. Also sensitivity to salt intake will be considered as an example of pharmacogenetics. The identification of genetic markers of drug response will help to achieve a better control of blood pressure in the population, by allowing a better tailor of antihypertensive therapy to individual patients.