This study examined the relationship of principal and assistant principal leadership style in shaping teachers' perceptions of their schools as professional learning communities. The researcher proposed that the traditional distinctions between the classic modes of leadership, namely, transactional and transformational modes of leadership, are difficult to interpret within the framework of professional learning community without considering the interaction of the principal and assistant principal leadership roles. Using Leithwood's (1992, 1993, 1994) definitions of leadership as transformational and management as transactional, empirical evidence from 81 schools is presented that supports the need for both leadership and management skills in the development of a professional learning community. The data also suggest that the principal alone need not be responsible for both. A leadership model for principals and assistant principals with complementary transactional and transformational modes of leadership styles is advanced.