The cerebral blood flow is tightly regulated by myogenic, endothelial, metabolic, and neural mechanisms under physiological conditions, and a large body of recent evidence indicates that inflammatory pathways have a major influence on the cerebral blood perfusion in certain central nervous system disorders, like hemorrhagic and ischemic stroke, traumatic brain injury, and vascular dementia. All major cell types involved in cerebrovascular control pathways (i.e., smooth muscle, endothelium, neurons, astrocytes, pericytes, microglia, and leukocytes) are capable of synthesizing endocannabinoids and/or express some or several of their target proteins [i.e., the cannabinoid 1 and 2 (CB1 and CB2) receptors and the transient receptor potential vanilloid type 1 ion channel]. Therefore, the endocannabinoid system may importantly modulate the regulation of cerebral circulation under physiological and pathophysiological conditions in a very complex manner. Experimental data accumulated since the late 1990s indicate that the direct effect of cannabinoids on cerebral vessels is vasodilation mediated, at least in part, by CB1 receptors. Cannabinoid-induced cerebrovascular relaxation involves both a direct inhibition of smooth muscle contractility and a release of vasodilator mediator(s) from the endothelium. However, under stress conditions (e.g., in conscious restrained animals or during hypoxia and hypercapnia), cannabinoid receptor activation was shown to induce a reduction of the cerebral blood flow, probably via inhibition of the electrical and/or metabolic activity of neurons. Finally, in certain cerebrovascular pathologies (e.g., subarachnoid hemorrhage, as well as traumatic and ischemic brain injury), activation of CB2 (and probably yet unidentified non-CB1/non-CB2) receptors appear to improve the blood perfusion of the brain via attenuating vascular inflammation. cerebral circulation; endocannabinoids; cannabinoid receptors; TRPV1 channel; neurovascular unit THE CEREBRAL VASCULATURE HAS two main homeostatic functions: 1) to adjust the local blood supply to the eventually rapidly changing metabolic demands of neurons; and 2) to maintain an optimal extracellular environment in the brain. The former function is realized by the regulation of the local cerebral blood flow (CBF), whereas the latter is achieved by the maintenance of the blood-brain barrier (BBB) and related transport mechanisms. The endocannabinoid system has been implicated as an important regulatory component in both of these cerebrovascular functions. The roles of endocannabinoids and cannabinoid receptors in the BBB have been reviewed recently (237). Here we aim to overview our knowledge on the endocannabinoid-mediated regulation of cerebral circulation.