Molecular Organization and Assembly of the Postsynaptic Density of Excitatory Brain Synapses -- Molecular Organization and Assembly of the Central Inhibitory Postsynapse -- Molecular Organization and Assembly of the Presynaptic Active Zone of Neurotransmitter Release -- Extracellular Matrix and Synaptic Functions -- Electrical Synapses - Gap Junctions in the Brain -- Neuron-Glia Interactions at the Node of Ranvier -- Cognate Interaction Between Endothelial Cells and T Cells -- Impact of the Immunological Synapse on T Cell Signaling -- The Biophysics of T Lymphocyte Activation In Vitro and In Vivo -- Molecular Regulation of Cytoskeletal Rearrangements During T Cell Signalling -- Membrane-Proximal Signaling Events in Beta-2 Integrin Activation -- Regulation of Immune Cell Entry into the Central Nervous System -- Cell-cell communication by Endocannabinoids during Immune Surveillance of the Central Nervous System. At first glance, the nervous and immune systems appear very different. However, both systems have developed mechanisms for memory formation - though of quite different quality and significance for the organism. One striking example is that both systems form and communicate via synapses armed with similar sets of proteins. This collection of reviews, contributed by internationally recognized immunologists and molecular and cellular neurobiologists, puts side by side cellular communication devices and signaling mechanisms in the immune and nervous systems and discusses mechanisms of interaction between the two systems, the significance of which has only recently been fully appreciated.