The ultimate goal of second language acquisition research is to come to an understanding of what is acquired and the mechanisms which bring that knowledge about. In recent years, the attempt to understand these issues has come from varying perspectives: some researchers have been concerned with language development as it relates to conversation; others have dealt with the role of affect, while others have investigated first language influences on the process of second language acquisition. What has been lacking is a global and comprehensive view which shows how these various perspectives interlock. In this paper I sketch out such a view incorporating sociolinguistic, psycho-linguistic, and linguistic aspects of acquisition.
Within the proposed framework, there are five levels in a learner's conversion of ambient speech (input) to output: (1) apperceived input, (2) comprehended input, (3) intake, (4) integration, and (5) output. In this paper I expand upon each of these levels as well as explicate the factors which mediate between one level and another. In addition, I discuss implications for fossilization and variation as they relate to concepts presented.