Expressive arts group supervision is the use of music, stories, movement, poetry or prose, role-play or psychodrama, art, guided imagery, or play to help trainees develop reflective skills (Wilkins, 1995), express thoughts and feelings (Knill, Levine & Levine, 2005; Lahad, 2000), develop new perspectives (Gladding, 2005), increase communication between trainees and supervisors (Fall & Sutton, 2003), create success and cohesion (Neswald-McCalip, Sather, Strati, & Dineen, 2003), develop self-understanding (Lett, 1993, 1995), and foster creative skills (Lahad, 2000). Its use in counselor trainee supervision is relatively recent, and the research that explores its use with master's level trainees is limited. This study explored, through a phenomenological study, the in-depth experiences of master's level trainees in expressive arts group supervision to gain a better understanding of their feelings, thoughts, attitudes, understandings, and process through their rich, thick descriptions. These descriptions were obtained through reflection papers, observations, and individual interviews. The data was analyzed through Moustakas's (1994) phenomenological method, and the themes of expressive arts group supervision were explicated. The findings indicate that expressive arts group supervision is a holistic reflective process that occurs in four phases (a) initial reaction, (b) arts engagement, (c) reflection, and (d) transformation. Trainees experienced expressive arts group supervision as contributing to their personal and professional growth. [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.]