The Maturation Phenomenon, first described by Ito et al. in 1975, refers to post ischemic changes that develop hours or days after an ischemic insult. The delayed neuronal death of CAl pyramidal cells of the hippocampus is a classic example. The report of the phenomenon boosted research in the field, as it became evi dent that ischemic damage is not a sudden event but a process potentially suscep tible to therapeutic intervention. In September 1990, Ito and collaborators organized the First International Sym posium on "Maturation Phenomenon in Cerebral Ischemia" which was held in To kyo,...