This session presents development and validation of the Counseling Self-Efficacy Sources Scale (CSESS), a 25-item instrument assessing Bandura's four self-efficacy sources in counselor training. Findings from 271 counseling students demonstrate strong psychometric properties. The session also offers practical guidance on using CSESS profiles to inform teaching, supervision, and curriculum design. Attendees gain tools to assess and cultivate self-efficacy in counseling students.