This study tested the role of enabling school structures, collegial trust and academic emphasis in the development of professional learning communities (PLCs) in a low-income school district. The empirical study was based upon the perceptions of teachers and principals as provided by survey responses (N = 67 schools). While enabling school structures, collegial trust and academic emphasis simultaneously contributed to the explanation of PLCs, only structure and trust had a unique effect on PLCs with structure having the larger contribution.