Self-determination, the concept that individuals are qualified to make their own decisions about their lives, is a central concept in the social work profession. It is described in the NASW Code of Ethics as one of a social worker’s primary ethical responsibilities, and it provides a framework for practitioners working with the many populations that social workers serve. Despite the NASW’s professional mandate, self-determination has been the subject of decades of discipline-wide debate. Proponents argue that self-determination is empowering and acknowledges that clients are the best resource on their own needs. Critics argue that one can never fully be self-determined and that social workers face an impossible dilemma: they must promote client self-determination while upholding societal and agency conventions, oftentimes, in contradiction with each other. Informed by the historical development of self-determination described in the professional social work literature, eleven, seasoned MSW level child welfare social workers were interviewed in a qualitative study. Participants were asked about how they conceptualized self-determination within their practice, and how they handle working with mandated clients whose rights and decision-making can be limited by the state or agency. In the interviews, workers described self-determination in terms consistent with the literature, and also revealed themes about conflicts that they experience within their job function. Participants also described similar factors that hinder their ability to promote self-determination in practice. The study revealed several newly emerging themes regarding factors that promote a worker’s ability to promote client self-determination in practice. These findings provide insight into how professional social workers engage and interpret the professional mandate of promoting self-determination in the field, and provide direction to help educate and prepare social workers to address key ethical dilemmas, and foster important relationships with clients facing agency mandates and societal oppression.