The truth of an utterance generally depends on what the words uttered mean and what is the current state of the world; but also on the context of the utterance. Within formal semantics this was first accounted for. by Kaplan, by means of explicating meanings as functions from contexts to intensions. Stainaker then brought the attention to the fact that utteraces not only ‘consume’ contexts but also ‘produce’ new ones; and that context is thus what mediates the interplay between subsequent utterances. In this paper we point out that context can be considered either from the viewpoint of the information it contains (which delimits what can be subsequently consistently claimed), or from the viewpoint of individuals which it contains (which determines what can be subsequently succesfully anaphorically referred to). We discuss the possibilities of explicating contexts within the framework of formal semantics and we also discuss the question to which extent contexts belong to semantics.