The complex and changing relationship between theory and practice in social work has received increasing attention in recent years. Parton (2000) has advocated a constructionist approach that underlines the similarity between the roles of the researcher and the practitioner. Personal construct theory (Kelly, 1955) is one member of the constructionist family that has particular implications for social work practice. It evolved as a pragmatic approach to psychotherapy, advocating a research supervisor/student model of the practitioner/client relationship. In this article, we elaborate its application to social work practice, drawing on contemporary work in the fields of trauma and loss to illustrate its value.