The identification and recruitment of effective school principals who can transform schools in the midst of today's chaotic economic, social, and global environments require a thorough understanding of the research on effective leadership. Current research indicates that principals who exhibit transformational leadership and, most recently, instructional leadership, are the most successful by all measures, including school climate, teacher empowerment, community support, and high student performance results. This study focused on a sample of principals from a population who recently received the distinction of a National Distinguished Principal (NDP) to determine if a correlation existed between their leadership dimensions and that of the effective principal leadership research. The use of a 360-degree survey instrument for this study provided valuable data about each principal's leadership from multiple sources. The following research questions guided this study: 1. How do NDPs rate their own leadership dimensions? 2. To what extent do the staff and stakeholders within the NDPs' school community identify the same or similar dimensions of leadership as the NDPs do of themselves? 3. To what extent do the NDPs' dimensions of leadership correlate with the key areas of effective school leadership established by the National Association for Elementary School Principals and the Interstate School Leaders Licensure Consortium? The results of this study showed discrepancies among the NDPs' perceptions of their own leadership dimensions and their raters' perceptions of their NDPs' leadership dimensions. In addition, this study revealed the NDPs' leadership strengths and needs and how those differed from the national standards for principal leadership. The three leadership tasks of most need for the NDPs, according to this study, were safety and organizational management for learning, instructional leadership, and change. This study could assist all public and private primary, secondary, and postsecondary educational institutions in their search, development, and retention of exemplary school principal leadership. The principal leadership dimensions identified in this study will be needed to lead the learning organizations of the 21st century and beyond. Four appendixes are included: (1) Importance of Leadership Tasks Self-Ranked by NDPs and All Raters; (2) Written Comments; (3) Top 20 NDP Leadership Strengths; and (4) Top 20 NDP Leadership Needs. (Contains 2 tables.)