The No Child Left Behind Act of 2001 increased the importance of having principals who are not only effective leaders of general education programs but knowledgeable and skilled in special education and able to effectively lead special education programs. The researcher examined four principals of elementary schools (i.e., kindergarten through fifth grades) in Alabama. Two principals (i.e., Case A and Case B) were identified as being knowledgeable and skilled in special education, and two principals (i.e., Case C and Case D) were identified as being marginally knowledgeable and skilled in special education. The purpose of this study is to determine the similarities between how principals who are knowledgeable and skilled in special education lead and support the special education programs at their schools, to examine the differences between how those principals and principals who are identified as marginal in their knowledge and skill in special education lead and support special education programs at their schools, and examine the role that the principal who is knowledgeable and skilled in special education plays. This study attempts to gain a deeper understanding of the constructs of effective special education leadership at the school level. A sequential mixed-methods process was used to collect data. The researcher used a survey to collect data during Phase 1 that was analyzed through the use of descriptive statistics within-case and a means comparison across cases. In Phase 2, data were collected from (a) archival records, (b) interviews, (c) documentation, and (d) direct observations. Data were analyzed through a within-case analysis through coding, categorizing, and identifying emerging themes. Data were analyzed through a cross-case analysis for similarities between principals who are knowledgeable and skilled in special education and then between principals who are marginally knowledgeable and skilled in special education. Then differences between the two groups where identified. Conclusions are drawn in five areas: (a) necessity of knowledge and skill in special education, (b) possession of knowledge and skill in special education, (c) the roles principals play as leader of the special education program, (d) how principals support special education programs, and (e) special education oversight at the school level. [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.]