Problem: While full-time faculty at any institution of higher learning undergo an established system of evaluation of teaching effectiveness, adjunct faculty members' experience varies greatly from institution to institution. There is little in the relevant academic literature about an effective feedback mechanism for evaluating teaching effectiveness among adjunct faculty members. Limited qualitative research has been done to understand the effects of teaching evaluations on the professional development and growth of individual adjunct faculty members. Developing an understanding of effective evaluation of teaching that will result in improved adjunct faculty professional development and growth will impact not only the faculty members' morale and retention but also student learning and student success. Method: The researcher used a grounded theory approach based on the data collected from semi-structured interviews with eight adjunct faculty members to understand a) what type of feedback of their teaching effectiveness adjunct faculty currently receive; b) what types of feedback of their teaching effectiveness adjunct faculty find to be helpful for professional development and growth; c) how adjunct faculty use the feedback of their teaching to shape their professional development decisions; and d) how the feedback of teaching effectiveness is perceived by adjunct faculty. Results: The results of the study led the researcher to form a substantive theory, Feedback Mechanisms for Sustainable Adjunct Faculty Growth, which states that the feedback that leads to sustainable adjunct faculty growth is (a) inspiration-led through exhibiting inspirational leadership; (b) relationship-building through promoting collegial collaboration; (c) learning-centered through fostering student success; (d) instructor-oriented through upholding the instructor agency; and (e) support-imparting through nurturing a culture of support. This model includes the multiplicity of voices and processes of the effective assessment of teaching and is framed in the context of contributing not only to the advancement of each individual adjunct faculty but also to the greater good of the academic community. Conclusions: The present study examined the results of feedback and evaluation of teaching effectiveness on adjunct faculty professional development and growth. The findings suggest that feedback that leads to sustainable adjunct faculty growth is inspiration-led, relationship-building, learning-centered, instructor-oriented, and support-imparting. The results have important implications for both teachers and administrators as they help adjunct faculty develop professionally, contribute towards a higher quality of teaching instruction, and improve student learning. [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.]