This longitudinal research investigated the interactive effect of social attachment style and perceived-counselor behavior on exploratory behavior exhibited by clients during and after career counseling. Results from 96 clients in career counseling indicated that social confidence and comfort, and the perception that the counselor had created social comfort and personal security, enhanced the range and effectiveness of career exploration by the client. The counselor's functioning as a "secure base" moderated the association between clients' avoidance and anxiety attachment style and their career exploration. Specifically, when the clients who were high in social avoidance or in social anxiety perceived-counselors as providing an atmosphere in which they feel secure, they engaged in career exploration far more than similar clients who did not perceive their counselor as a secure base. (Contains 2 figures and 1 table.)