Methods
Method-related problems derive from reliance on data sources that represent espoused theory rather than theory in use. As noted previously, the espoused theories surrounding instructional leadership remain contested and ambiguous. Further complicating the espoused theory issue is that most large-scale studies of instructional leadership, beyond demographic descriptions, generate data primarily through perceptual surveys of the school leaders and stakeholders in schools (Blase & Blase, 1999; Bryk ct al., 1999).