Nursing theories which have evolved from mental health-psychiatric nursing have focused on the individual nurse-client relationship Other nursing theories generally focus on the individual as client Therefore, nurses working with families may have difficulty in applying these frameworks to their practice Nursing theories need to be expanded to include families, groups and communities more explicitly The well established theory of Hildegard Peplau, which previous studies have found to be the theory most frequently used by psychiatric nurses, and the family systems nursing theory of Wright and Leahey share a complementary focus Both theories form part of the interpersonal paradigm of nursing, both view nursing from an interactional perspective, rather than focusing on individuals Use of a combined theoretical approach offers several advantages The approach explicitly considers both the individual and the family The combination provides grounding for family work in an articulated nursing theory