The purpose of this study was to determine to what extent a relationship existed between student achievement and how teachers and principals assess leadership effectiveness in 29 Alabama schools. This study also investigated the extent to which teacher and principal tenure were related to their perceptions of leadership and to student achievement. The population for this causal comparative study included 29 principals and 785 teachers who completed an Alabama pilot of the Vanderbilt Assessment of Leadership in Education (VAL-ED) in 2009-2010. This study used four sources of data: the VAL- ED, the Alabama Reading and Math Test (ARMT), the Alabama High School Graduation Exam (AHSGE), and information on teacher and leader tenure from the Alabama State Department of Education. Findings indicated that teachers and principals agreed overall on the level of performance for each of the 29 principals in the study. Although principals agreed that the VAL-ED Core Component of "Quality Instruction" was the most important, there were no relationships found between principal scores on "Quality Instruction" and student achievement. The strongest relationships existed between teachers' scores on the VALED Core Components and Key Processes and 11th grade student achievement in reading and mathematics. Weak or no relationships existed between teacher scores on VAL-ED and 5th or 8th grade student achievement. There were moderate, positive relationships between principals' scores on the VAL-ED Core Components and Key Processes and student achievement in 8th and 11th grades. Weak or no relationships existed between principal scores on VAL-ED and 5th grade student achievement. There were few relationships between the scores given on VAL-ED, teacher or principal tenure, and student achievement. There was a moderate, positive relationship between principal tenure and their VAL-ED scores on "High Standards". Also, there was a moderate, positive relationship between principal tenure and 8th grade reading and mathematics scores and with 11th grade mathematics scores. Additionally, a moderate, positive relationship was indicated between teacher tenure and scores in 5th grade reading. [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.]