In this paper, we discuss the theoretical and methodological issues in exploring identity and agency within a narrative of choosing mathematics. Taking as our starting point Bakhtin's emphasis on the dialogic space between interlocutors, we explore how an awareness of the addressivity and otherness of utterances, and of the role of genre and heteroglossia in self-authoring, can be used in the analysis of an interview to gain insight into one student's narrative of choosing mathematics despite the fear that it held for her. We consider how our own research preoccupations with the role of gender and family discourses in learners' relationships with mathematics played a part in the interview, and how the interviewee's appropriation of, and resistance to, these and other genres can be understood as an assertion of agency within her particular narrative of choice.