This case study examined action research conducted by bilingual education teachers in urban schools as a tool for progressing from novice-to-expert teachers. We described a longitudinal study across four cohorts of first-year bilingual education teachers as action researchers (n = 9). The study investigated the following: (1) how school leaders and colleagues responded to knowledge (innovations) generated through practitioner inquiry; and (2) teacher-researchers' perceptions about the process and outcomes of sharing their research findings with school leaders and colleagues. Findings clustered around two patterns: feelings of teacher self-efficacy and workplace isolation. Principals perceived innovations as human capital, not social capital.