Aim: This paper examined nurses' levels of satisfaction with their supervisor-subordinate communication relationships on their level of role ambiguity (in relation to their supervisors) and their resultant perceptions of autonomy and in turn, affective commitment Methods: A survey of 900 nurses working in private sector hospitals in Australia was used to collect data. Results: The combined effects of supervisor-nurse communication relationships, nurses' role ambiguity in relation to their supervisors plus nurses' resultant perceptions of autonomy, definitely influenced nurses' level of affective commitment. Also, nurses were somewhat dissatisfied with their communication relationships with their supervisors, experienced role ambiguity, reported being only a little autonomous, and were subsequently only somewhat committed to their hospitals. Contribution: The findings contribute to addressing nurse retention challenges by identifying factors affecting nurses' organisational commitment. Not only will nurses be more productive (with less supervisor ambiguity), but high quality NUM-nurse communication relationships are also likely to enhance perceptions of autonomy and thereby, encourage nurses' commitment to their organisation and intention to remain. Implications: These results raise the question as to whether the present management practices are ideal for retaining nurses who are in short supply in many Organisation for Economic Co-operation and Development countries.