The study of sphingolipids has undergone a renaissance over the past decade due to the realization that these lipids are involved in a variety a biological processes, such as differentiation, apoptosis, cell growth, and cell migration. In the nervous system, sphingolipids, particularly gangliosides, have attracted particular attention as they occur at high levels and their levels change in a developmentally regulated program. Despite the fact that a large body of data has accumulated on the expression and metabolism of individual gangliosides within specific brain regions, the role of individual gangliosides in neuronal development is still poorly understood, and their specific functions are only now beginning to be elucidated. In the present article, we discuss various aspects of our current knowledge concerning the involvement of sphingolipids and gangliosides in neuronal development, and then discuss some recent findings that shed light on the role of sphingolipids and gangliosides obtained with animal models of sphingolipid and other lysosomal storage diseases.