This volume brings together studies dealing with second language learning in contexts that provide intensive exposure to the target language. In doing so, it highlights the role of intensive exposure as a critical distinctive characteristic in the comparison of learning processes and outcomes from different learning contexts: naturalistic and foreign language instruction, stay abroad and at home, and extensive and intensive instruction programmes. The different chapters represent a wide range of learning contexts and types of learning, as well as different approaches that yield much needed evidence on the role of context of acquisition in second language learning.