The neuronal cell adhesion molecule neurofascin is expressed in highly complex temporally and spatially regulated patterns. Accordingly, many different functions have been described including control of neurite outgrowth, clustering of protein complexes at the axon initial segments as well as at the nodes of Ranvier and axoglial contact formation at paranodal segments. At the molecular level, neurofascin provides a link between extracellular interactions of many different interaction partners and cytoskeletal components or signal transduction. Such interactions are subject to intimate regulation by alternative splicing and posttranslational modification. The versatile functional aspects of neurofascin interactions pose it at a central position for the shaping and maintenance of neural circuitry and synaptic contacts which are implicated in nervous system disorders.