School counseling interns are on the boundary of communities of practice. This study explored how school counselors develop competence during internship experiences by analyzing an online dialogue taking place among a small group of interns. Feelings of being on the boundary intensified with unsatisfactory supervisor-intern relationships (lack of mutuality of engagement) or when interns experienced a sense of powerlessness to effect change at their internship placements (negotiating their repertoire). As boundary dwellers, interns turned to peers to make sense of their experiences (accountability to the joint enterprise). Implications include the importance of the supervisor-intern relationship and the relationships among internship peers.