We retrospectively reviewed the clinical and radiologic characteristics of 17 individuals with septo-optic dysplasia (SOD) and attempted to identify correlations between imaging findings, clinical features, and neurodevelopmental outcome. Surprisingly, only 1 (6%) individual was classified as classic SOD (with septum pellucidum/corpus callosum dysgenesis), 3 (18%) as SOD-like (with normal septum pellucidum/corpus callosum) and the majority, 13 (76%), as SOD-plus (with cortical brain malformation). Cortical abnormalities included schizencephaly, polymicrogyria, and gray matter heterotopias. All individuals had optic nerve hypoplasia, 11 (65%) had endocrinologic deficits, and 13 (76%) had abnormal cerebral midlines. Seven individuals (41%) had all 3 features. Neurodevelopmental outcome was abnormal in 13 (78%), ranging from mild to severe developmental delay. Individuals with SOD-plus did not have more severe neurologic deficits than individuals with classic or SOD-like subgroups. Thus, SOD is clinically and radiologically heterogeneous, and cortical abnormalities are very common. Neurodevelopmental deficits are very prevalent, and of wide-ranging severity.