The function of the adult nervous system is dependent upon trillions of neural connections. In order to establish proper neural connectivity, organisms must generate appropriate numbers of neurons and glial cells. Moreover, neurons must extend axons, elaborate dendrites, and form synapses with their partners. At Johns Hopkins, our neuroscience laboratories focus on both vertebrate and invertebrate systems, and use sophisticated genetic, biochemical and cellular tools to study neural development. Areas of interest include stem cell biology, cell proliferation and migration, differentiation of neurons and glia, cell survival and apoptosis, mechanisms of axon and dendrite growth and guidance, and synapse formation and elimination. Recent discoveries include the identification of novel ligand-receptor complexes that control axon guidance, molecular mechanisms underlying CNS synapse formation, and the molecular basis of motor neuron differentiation. These advances provide exciting opportunities for research focused on the treatment of developmental disorders and may ultimately facilitate repair of the injured nervous system.