Studies in the intensive care unit (ICU) suggest that better communication between families of critically ill patients and healthcare providers is needed; however, most randomized trials targeting interventions to improve communication have failed to achieve family-centered outcomes. We aim to offer a novel analysis of the complexities involved in building positive family-provider relationships in the ICU through the consideration of not only communication but other important aspects of family-provider interactions, including family integration, collaboration, and empowerment. Our goal is to explore family members' perspectives on the enablers and challenges to establishing therapeutic alliance with ICU physicians and nurses.We used the concept of therapeutic alliance as an organizational and analytic tool to conduct an interview-based qualitative study in a 20-bed adult medical-surgical ICU in an academic hospital in Toronto, Canada. Nineteen family members of critically ill patients who acted as substitute decision-makers and/or regularly interacted with ICU providers were interviewed. Participants were sampled purposefully to ensure maximum variation along predetermined criteria. A hybrid inductive-deductive approach to analysis was used.Participating family members highlighted the complementary roles and practices of ICU nurses and physicians in building therapeutic alliance. They reported how both provider groups had profession specific and shared contributions to foster family communication, integration, and collaboration, while physicians played a key role in family empowerment. Families' lack of familiarity with ICU personnel and processes, physicians' sporadic availability and use of medical jargon during rounds, however, reinforced long established power differences between lay families and expert physicians and challenged family integration. Family members also identified informal interactions as missed opportunities for relationship-building with physicians. While informal interactions with nurses at the bedside facilitated therapeutic alliance, inconsistent and ad-hoc interactions related to routine decision-making hindered family empowerment.Multiple opportunities exist to improve family-provider relationships in the ICU. The four dimensions of therapeutic alliance prove analytically useful to highlight those aspects that work well and need improvement, such as in the areas of family integration and empowerment.