The terms leadership and leader development are often used synonymously. However, there are different outcomes and needs associated with each type of development. Even with these differences, both types of developments may be needed to help individuals master leadership skills effectively. This study explored the critically formative processes and influences contributing to a leader's leadership formation and development. A framework of adult cognitive development, identity development, and spiritual development offered areas where an individual may need development for leadership, while a framework of social cognitive theory, andragogy, and transformational learning offered insights into the process of development and transformation. By using phenomenography as the research method, this study aimed to find the variation of the phenomenon and describe leadership development as the participants experienced it. This information may help organizations and individuals who are trying to develop future leaders understand critically formative processes and influences contributing to a leader's leadership formation and development. The research found four categories related to the participants' leadership development experiences within Leadership Tuscarawas and one category based on past experiences outside of the program. These categories were: (a) learning from others, (b) becoming aware, (c) building relationships, (d) emotions and feelings, and (e) leadership development experiences. Each category gave insights into what Leadership Tuscarawas alumni experienced within a leadership development program. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]