© 2016 Elsevier Ltd All rights reserved. The immunological synapse refers to the stable interface between immune cells organized by adaptive or innate immunoreceptors in concert with adhesion molecules. Another mode of interaction that allows immunoreceptor function during relative motility between the two cells is referred to as a kinapse. One of the most important functions of the immunological synapse or kinapse is integration of innate and adaptive signals to decide if initiation of an immune response or an effector program is appropriate following specific antigen recognition. The immunological synapse and kinapse have structural modules that are shared, but differently configured to achieve radial symmetry for a synapse or asymmetry for a kinapse. Model immunological synapses have three major compartments referred to as supramolecular activation clusters or SMACs. The distal or dSMAC is analogous to a sensory lamellipodium, the peripheral or pSMAC is analogous to an adhesion molecule rich lamella, and the central or cSMAC is analogous to the uropod. T cell receptor (TCR) microclusters are formed in the dSMAC and translocated toward the inner edge of the pSMAC in an F-actin-driven process. The cSMAC is then formed through a sorting mechanism mediated by the endosomal sorting complexes required for transport, which generates a CD28-enriched endo-cSMAC and a TCR-enriched ecto-cSMAC. The cSMAC is also the site of a secretory or exo-cSMAC that can inject cytokines, cytolytic agents, and exosomes into the synapse center. Kinapses are threefold less efficient in delivering cytolytic agents to target cells. In vivo analysis of T cell-antigen-presenting cell interactions suggests that both synapse and kinapse modes of interaction are employed. Stable synapses are important in regulation of immune response decisions and for efficient effector function.