The primary purpose of this study was to determine if a difference exists among small and large Texas public school district superintendents regarding which personal characteristics and professional skills are perceived to define effective superintendents. Superintendent personal characteristics and professional skills were assessed using a modified version of the Superintendent Effectiveness survey, originally developed by McCormick (2011). The modified Superintendent Effectiveness survey was comprised of three sections: (a) demographics, (b) 14 personal characteristics, and (c) 21 professional skills. Texas public school superintendents were instructed to rate the extent to which each personal characteristic and professional skill defines an effective superintendent using a five-point Likert scale. The ordinal data for each of the 35 Likert items were summed and ranked from highest to lowest revealing an overlap of four out of five of the top five ranked personal characteristics and professional skills that are needed to be effective by large and small school district superintendents. Results of the Mann-Whitney U analysis revealed no statistically significant differences in the degree to which personal characteristics and professional skills categorically are needed to be effective in large vs small school superintendents. Additionally, no statistically significant differences were revealed between how large and small school superintendents ranked each of the fourteen personal characteristics in terms of importance to being an effective superintendent. With regard to professional skills, the Mann-Whitney U test revealed that large school superintendents associated a statistically significant higher amount of importance in terms of being an effective superintendent to four specific professional skills than their small school counterparts: (a) allocates resources to support academic goals (p < 0.025), (b) aware of political impact on education (p < 0.01), (c) connects and builds community partnerships (p < 0.025), and (d) monitors/assesses academic goals (p < 0.025). [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.]