 This is a multicenter, placebo controlled, randomized, double blinded Phase 2 study in 100 subjects 18-90 years of age who have sustained a recent ischemic stroke. Potential subjects can be screened and consented the day of their stroke Day 1. Treatment with umbilical cord blood UCB cells or placebo will be administered intravenously as a single infusion as early as 3 days but no later than 10 days after the patients stroke. UCB units will be selected from an accredited U.S. public cord bank based on blood type, race and a targeted cell dose ranging between 0.5 to 5 x 107 total nucleated cell count TNCCkg. Study subjects will not receive immunosuppressive or myeloablative medications prior to infusion of the cord blood or placebo. 