The author argues that second language acquisition (SLA) theorists have struggled to conceptualize the relationship between the language learner and the social world because they have not developed a comprehensive theory of social identity which integrates the language learner and the language learning context. She also maintains that SLA theorists have not adequately addressed how relations of power affect interaction between language learners and target language speakers. Using data collected in Canada from January to December 1991 from diaries, questionnaires, individual and group interviews, and home visits, the author illustrates how and under what conditions the immigrant women in her study created, responded to, and sometimes resisted opportunities to speak English. Drawing on her data analysis as well as her reading in social theory, the author argues that current conceptions of the individual in SLA theory need to be reconceptualized, and she draws on the poststructuralist conception of social identity as multiple, a site of struggle, and subject to change to explain the findings from her study. Further, she argues for a conception of investment rather than motivation to capture the complex relationship of language learners to the target language and their sometimes ambivalent desire to speak it. The notion of investment conceives of the language learner, not as a historical and unidimensional, but as having a complex social history and multiple desires. The article includes a discussion of the implications of the study for classroom teaching and current theories of communicative competence.