This study used identity as a framework to understand how preservice science teachers develop the reform-minded ideas inherent in science-specific reforms. Six participants systematically reflected about their reform-based and field lessons taught during a methods course and field lessons taught during student teaching. Patterns in their reflections revealed five different lenses they used to propose changing their practices and negotiate the dissonances those proposals created with their core conceptions about teaching. The extent to which participants expressed reform-minded thinking and enacted science-specific reforms in the field was associated with how they used the lenses to resolve dissonances. The findings suggest why preservice teachers need explicit opportunities to engage in work to cultivate the reform-minded identities required to enact science-specific reforms.