The immune synapse is central to the regulation of T-cell activation and effector functions. Vesicular compartments dynamically interact with the immune synapse. Here they take part in the trafficking of signaling components to and from the synaptic cleft, as well as in the directed delivery and release of T-cell effector compounds. In addition to ferrying cargo, emerging evidence indicates that vesicular compartments at the immune synapse are actively involved in the signaling processes which underlie T-cell activation, specifically that they productively interact with signaling microclusters at the synapse, or become sites of signaling themselves. How different classes of sub-synaptic vesicular compartments associate with the immune synapse and to what extent they influence the processes there remains only partially understood. I here discuss the mechanisms underlying the interactions between vesicular compartments and the immune synapse and the contributions such interactions have on T-cell activity, with particular focus on the advantages to the regulation of T-cell signaling.