This article argues that prospective teachers who have the most productive experiences within pre-student teaching field experiences are those whose field sites allow them to become members of communities of practice, the conditions of which, according to Wenger (1998) include joint enterprise, mutual engagement, and shared repertoire. Employing interviews and content analysis of documents, the researchers explored the experiences of a cohort of teacher candidates in a pre-student teaching practicum to better understand elements of field experience that might influence identity development. We highlight the cases of two prospective teachers as illustrative and contrasting experiences of the cohort as a whole. We conclude by offering recommendations for how teacher education programs might assist prospective teachers with negotiating for conditions within field sites that allow for productive participation and growth.