The renin angiotensin aldosterone system (RAAS) has been implicated in the pathogenesis of cerebrovascular diseases. During the past decades, AU: INCLUDE A NUMBER? RAAS has gained attention as an important therapeutic target in cardiovascular medicine. Modulation of the RAAS for primary and secondary stroke prevention seems an appealing strategy. Several experimental studies have showed that pre-treatment with RAAS inhibitors prior to the initiation of ischemia exerts favorable effects on infarct volume, brain edema, and cerebral blood flow in the marginal zone. Furthermore, the activation of angiotensin receptor type 2 has been associated with neuroprotective effects. Accumulating evidence based on recent clinical trials indicate that blockade of RAAS has a potential role in stroke prevention. This review summarizes the pathophysiological aspects of brain RAAS and its constituents, presents experimental data on the neuroprotective actions of RAAS inhibitors and available evidence regarding their effects on stroke risk, and discuss future directions for research.