This quantitative study focused on the differences in perceptions between Illinois K-12 unit district public school superintendents and board presidents as to those performance competency indicators in the "Illinois Professional Standards for School Leaders" that they perceived as being most critical for superintendent success. Via a web-based, online survey, participants responded to six demographic questions and scored each of the performance competency indicators to their level of agreement regarding the importance of that performance competency indicator for success. Summing up the top three performance indicators for all respondents, for all superintendents and board presidents (male and female), the number of performance competency indicators was reduced from 63 down to a composite group of ten. All groups selected the performance competency of "having high expectations for all" as being a top indicator. Standard One which stresses vision, mission, goals, climate, and culture proved to be the most important standard for superintendents, with six out of ten of the performance competency indicators coming from that standard. Both role and gender were associated with the selection of the performance competencies. Specifically, the role of board president was associated with the selection of "provides a respectful, fair climate," and the role of superintendent was associated with the selection of "obtains resources for goals." Regarding the impact of gender, men selected "models core beliefs and takes actions to achieve goals," while being a female impacted the selection of "promotes academic excellence." Implications and recommendations for further research include concentrating superintendent development and evaluation on the ten shared performance indicators and replicating this study in other states that have adapted or adopted the ISLLC Standards or with a random sample nationwide. [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.]