A study researched the impact of the portfolio development process as an instructional strategy that promotes increased critical thinking, organization, communication, and self-reflection abilities. The inquiry began with a case study of eight adult learners representative of the student population of a nontraditional undergraduate program with a portfolio component. Of 1,227 students, 348 responded to a 24-question survey using a 4-part Likert-type scale to assess students' portfolio experiences. Findings indicated, after developing a portfolio, adult students expressed a change in their understanding of their abilities and of themselves; gained learning competencies in enhancement of communication and organizational skills, a deeper reflective process, and greater understanding of how they accomplished what they did in their personal and professional lives; and better understood the role of work in their lives. Students valued the constructs of leadership/personal learning and of work-related learning, their respective survey items, and the learning obtained from engaging in the portfolio process. Findings indicated the portfolio's potential as an instructional tool to identify prior learning and engender increased competencies in many areas, including skills in organization, writing, critical thinking, and self-reflection. (Appendixes include 32 references, survey, and survey results.) (YLB)