Where do the names of Greek gods come from? Do the names used by the Greeks to address their gods correspond to their "true" names, taught to the Greeks by the gods themselves? Or are they mere conventions that please the gods? Leaving aside philosophical debates, and especially Plato's views, which are already wellknown, this contribution will not only consider the famous Herodotean passages that explicitly address the question of the origin of the gods' names, but will also take into account other sources that implicitly hint at their origin. How are divine names treated in Homeric and Hesiodic poetry? In foundation myths of sanctuaries, found in Pausanias and other sources, who names the gods? What role do oracles play in establishing new divine names for later cult foundations? In the case of divine epiphanies, how are the deities recognised and their name determined?