Background: Institutional theorists suggest environmental stakeholders in the "organizational field" have a symbiotic relationship with governing agencies, leading to institutional isomorphism. Hence state policy makers copy the work of their colleagues across states to create a sense of legitimacy, certainty, and professionalization rather than developing policy based on metrics of efficiency and/or effectiveness. It can stifle innovation. The purpose of this study was to investigate the trends in state policy for school-based education administrators as an indicator of institutional isomorphism. Research Design: A "cohesive leadership system" for school leaders that has been operationalized by researchers through a five-segment continuum of standards, preparation program approval, assessment and licensure, mentoring and induction, and ongoing professional development coupled with licensure renewal. Researchers in this study reviewed published state regulations in all 50 states with respect to each of these five segments. Findings: Key trends include universal standards-based preparation, continuous renewal, increasing assessment and accountability, a wider breadth of providers for administrator development, tiered licensure, and renewal linked to school improvement, as measured by student standardized assessments. The establishment of the continuum itself as well as the trends within each facet of the continuum reflect high degrees of field conformity (isomorphism) and diminishing policy space for alternative paradigms. Conclusions: This trend is likely to continue because of the tight coupling of the environmental field related to educational administration. The conclusions suggest methods for injecting change into state policy to ensure advances in the field rather than simply replication of the status quo. (Contains 5 tables.)