School counselors may choose to pursue clinical supervision after they graduate from a master's program even though they are not required to do so. This quantitative study utilized a survey research design to examine the differences between school counselor professional identity (SCPI) development and post-master's supervision. Results from this study indicate significant differences in components of SCPI between school counselors who participated in post-master's supervision and those who did not. School counselors who pursued post-master's supervision had stronger identity scores focused on roles and responsibilities, leadership, and social justice advocacy.