A 3 year-old boy with gait-induced seizures is reported from University of Navarra, Pamplona, Spain. His father and grandmother had primary generalized epilepsy. He sat late at 12 months and walked late at 26 months. After recovery from a febrile illness at 2 years 10 months, he developed jerking of the left lower limb, impairing is ability to walk. EEG showed right parietooccipital spikes, and generalized S/W in sleep. While walking, slow S/W rhythmic discharges at C4 correlated with jerking of the left leg. At rest, the discharges resolved. MRI was suggestive of polymicrogyria in right frontal area. Ictal SPECT showed hyperperfusion on the right side with walking. After valproate therapy for 3 weeks, jerking decreased and walking ability improved.