Patent foramen ovales (PFOs) are common congenital cardiac defects that have been associated with the occurrence of stroke, especially with cryptogenic stroke, or those of undefined cause, accounting for up to 40% of all ischemic strokes. A number of studies have demonstrated the association of larger PFOs with increased shunting in patients with cryptogenic strokes. Medical treatment is often considered inadequate, and percutaneous closure offers an attractive, albeit controversial, alternative in stroke patients with PFOs. Although it is plausible that percutaneous PFO closure will reduce the rate of recurrent stroke in these patients, no prospective, randomized trials examining the efficacy of closure devices in this setting have been completed. This paper reviews the known relationship between PFOs and cryptogenic strokes and discusses current therapeutic options, including percutaneous closure.