The hereditary nature of familial hypertension has been clearly established by a number of clinical studies. Most of the present work has been concentrated on the correlation between various phenotypic traits and the level of blood pressure. The development of molecular genetics allow now to establish a link between high blood pressure and specific phenotypes. As analyzed in this paper, several strategies can be used for the genetic study of arterial hypertension: linkage studies in informative families, population association studies, analysis of subjects with contrasted predisposition to high blood pressure, affected sib-pair method. The identification of the loci implicated in blood pressure regulation and which contribute to the development of arterial hypertension can then be performed in this clinical material by two main approaches. One is based on the study of candidate genes, genes whose products are known to participate in blood pressure regulation, such as those of the renin-angiotensin system which are examplified. The other involves testing a series of markers distributed randomly throughout the genome in order to establish a link between increased blood pressure and a particular region of the genome.