Abstract : The aim of these lectures is to provide a survey of some significant advances in philosophy of language, starting from the early days of Montague, Lewis or Kaplan, when philosophy of language and natural language semantics still formed a unified discipline, itself grounded in logic, to the present days. I focus on the topic of context-dependence, covering the standard accounts of indexicality (Kaplan and followers), and comparing them to some less standard accounts, such as two-dimensional update semantics (Stalnaker and followers) or situation semantics (Barwise & Perry and followers). I will also look at certains forms of context-dependence that do not seem to be reducible to indexicality, and examine to which extent they motivate a departure from traditional truth-conditional approaches (as has been defended, on different grounds, within contextualist as well as relativist approaches to semantics).