Computational fluid dynamics (CFD) simulations have been introduced to enable individualized risk prognosis for patients with unruptured cerebral aneurysms. The present contribution provides an overview of the biomechanical and physiological principles of aneurysm formation and rupture. It describes the computational steps of the CFD and the evaluated parameters. The clinical value of CFD is then discussed based on a recent literature review. Finally, we discuss current methodological limitations and possible future developments to overcome the actual drawbacks of CFD.