This study was conducted to advance knowledge by examining the reasons that motivate teachers to participate in professional development and the relationship to teacher job satisfaction and retention in Christian-based K-12 Association of Christian Schools International (ACSI) member schools. The study contributes to the literature in the field because of very limited research on Christian-based schools, especially with regards to professional development, job satisfaction and retention. The study was a quantitative, non-experimental, correlational research design using two instruments, i.e., the Participation Reasons Scale (PRS) and the Job Satisfaction/Retention/Demographic Survey. The PRS scores indicated that the motivating factors for teachers to participate in professional development in rank order were: (a) professional commitment and reflection; (b) professional improvement; (c) personal benefits; (d) professional service; and (e) collegial learning. However, the PRS results did not reveal a significant correlation to job satisfaction or retention. In addition, the data related to on-line versus face-to-face delivery format, gender, marital status, age, level of education, years in education, and years in K-12 do not predict teacher participation in professional development opportunities. [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.]