In many countries in the world, English is identified as a foreign language with no official status but is increasingly used as the language of wider communication. In a number of these countries it is common that English is learned as a third language. Recent psycholinguistic research on third language acquisition and trilingualism has made clear that the acquisition of an L3 shares many characteristics with the acquisition of an L2 but it also presents differences. Accordingly, the educational aspects of teaching English as an L3 differ from those of teaching English as an L2 and have more implications concerning the optimal age for the introduction of the different languages and the desired level of proficiency in each. In the Basque Country there are two official languages, Basque and Spanish, and English is taught as a third language. Several projects have been carried out in order to improve proficiency in English: the early introduction of English in kindergarten, the use of content based approaches, and the use of English as one of the languages of instruction. This chapter describes the characteristics of these projects and discusses their outcomes as they relate to specific research conducted on third language acquisition.