Undoubtedly, different learning contexts offer different opportunities for foreign language practice. This article focuses on context effects, and reports on the findings of the "Study Abroad and Language Acquisition" (SALA) project, which has examined in depth the impact of two learning contexts, SA within the European Community Action Scheme for the Mobility of University Students (ERASMUS), and formal instruction (FI), on the progress made by advanced level higher education (HE) English as a foreign language (EFL) learners. The differential context effects on learners' EFL relative gains in oral and written skills are thus measured. Following a description of the European multilingual policies in the HE Area (HEA), each context is characterised from a second language acquisition perspective. When such effects on oral skills are analysed for the dimensions of Fluency and Accuracy, higher gains seem to accrue in the SA context than in the FI context in both dimensions, with the exception of phonological perception. When written skills are examined, for Complexity, Fluency and Accuracy, in a similar vein, benefits accrue to a larger extent after the period spent abroad, except for Complexity. To conclude, the overall superior effect on learners' linguistic progress of the SA context over the FI context is discussed.