The book concerns theoretical, interdisciplinary and methodological issues in L2 acquisition research. It gives an accurate and up-to-date overview of high quality work currently in progress in research methodology, processing, principles and parameters theory, phonology, the bilingual lexicon, input and instruction. The volume will have the purpose of a handbook for teachers, students and researchers in the area of second language acquisition. The aim is to provide the reader with an acquisition perspective on processes of second and foreign language learning.