A great number of modern neurophysiological studies give evidence about the possibility of the extrasynaptic diffusion of the released neurotransmitters. Such observations challenge the established view on synapses as isolated communication channels between pre- and postsynaptic neurones. In the present review article, we consider the latest experimental data on the interneuronal cross-talk mediated by extrasynaptic diffusion of L-glutamate (L-Glu) and gamma-amino-butyric acid (GABA). Possible physiological significance of this phenomenon is also discussed.