Abstract The purpose of this study was to examine differences, as perceived by supervisees, between supervisors employed within the same organization and their supervisees (“internal supervisors”) and supervisors employed outside their supervisees' organizations (“external supervisors”). It was hypothesized that differences would be found between them on factors related to “interferences” in supervisor-supervisee communication. As expected, external supervisors were found to provide more constructive criticism to supervisees than internal ones, to carry out more confrontation when necessary and appropriate, and to possess more expert-based authority (based on knowledge and skills) and less formal authority. No significant differences between the two groups were found regarding role ambiguity and conflict of supervisors.