In this paper we adopt the Selten–Pool [Selten, R., Pool, J., 1991. The distribution of foreign language skills as a game equilibrium. In: Selten, R. (Ed.), Game Equilibrium Models, vol. 4. Springer-Verlag, Berlin, pp. 64–84] framework of language acquisition based on “communicative benefits” derived from the ability to communicate with other speakers of an acquired language, and “learning costs” incurred by acquiring a foreign language. We show that, under some mild conditions, there exists a unique interior linguistic equilibrium. We then derive demand functions for foreign languages, that we estimate for English, French, German and Spanish in 13 European countries and demonstrate that the properties of these functions are consistent with...