Bioluminescence evolved in the natural world to enable communication among organisms via light in very dark environments, with one entity emitting and another sensing photons. It was unclear until recently whether bioluminescence is a feasible means of communication at the cellular level. Cell-to-cell communication via light transmission has been realized in several bioluminescent optogenetic applications. In the broadest sense, light-based communication between cells involves the generation of a light signal in one cell and its reception and translation into a response in another cell. Several different strategies have been employed to achieve such light-induced communication in synthetic cell systems. Bioluminescence-mediated communication between mammalian cells was used for the detection and transcriptional readout of trans-cellular interactions. Three strategies have been developed to control synaptic transmission between neurons. In two, luciferase-generated bioluminescence in a presynaptic neuron is used for activation of optogenetic elements in a postsynaptic neuron across the synaptic cleft, while another approach utilizes presynaptically released neurotransmitters to reconstitute a split luciferase for activating a fused opsin expressed in postsynaptic neurons. This overview chapter outlines the different approaches to light-induced communication. The three chapters following this overview chapter detail distinct strategies developed for bioluminescence-driven neuronal communication.