The paper is devoted to an econometric analysis of learning foreign languages in all parts of the world. Our sample covers 193 countries and 13 important languages. Four factors significantly explain learning, two of which affect the broad decision to learn, while two concern as well the choice of the particular language to learn. Literacy generally promotes learning while the world population of speakers of the native language generally discourages it. Trade with speakers of a specific language prompts learning of that specific language while the linguistic distance between the home and the foreign language discourages learning of the specific language. Trade is highly significant and may well deserve more emphasis than the other three key variables (literacy rate, linguistic distance, and world population of native speakers) because its direction can change faster and by a larger order of magnitude. Controlling for individual acquired languages, including English, is of no particular importance.