This study built and expanded on previous school leadership research by exploring the middle school teachers' perceptions of effective leadership behaviors. Semi-structured interviews comprised of schoolteachers working in Florida's Marion County public middle school grades six to eight were examined using a qualitative analysis. Results suggested that participants believed school leadership was important in encouraging teacher motivation. Middle school teachers significantly chose collaboration as a school leader practice that best supports teacher job performance. Collaboration was followed by coaching, championing, and engagement. These four essential school leader behaviors are defined and characterized, as well as four potential mediating factors (i.e., hope, thankfulness, confidence, respect), from which a thematic framework of leader behaviors thought to support teacher effectiveness emerged. In the broader context of leadership theory, specifically transformational, servant, authentic, and adaptive leadership theories, we investigate these four crucial school leader behaviors and mediators. This study's main contribution is the discovery of a set of leadership behaviors that are probably more effective in secondary schools because they were based on perceptions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]