Objective: This mixed methods systematic review examines the effectiveness and family experiences of interventions that promote partnerships between parents and the multidisciplinary health care team in pediatric and neonatal intensive care units. Introduction: The hospitalization of a child or infant in an intensive care unit can have considerable negative effects on them and their family. Family members can experience increased stress, anxiety or depression and detrimental impacts on quality of life and family functioning. Interventions that promote families as health care partners may improve negative outcomes arising from intensive care hospitalization. Inclusion criteria: The review will include family members of pediatric or neonatal patients hospitalized in an intensive care unit. It will focus on interventions that promote partnership between families and multidisciplinary health care teams in pediatric and neonatal intensive care units and the family's experiences of these interventions. The outcomes of interest are stress, anxiety, depression, quality of life, family functioning, family empowerment or satisfaction with family-centered care. Methods: The proposed review will follow the JBI methodology for convergent segregated mixed methods systematic reviews. It will search for published and unpublished studies from eight different sources. Studies will be reviewed by title and abstract and potentially eligible studies will have full text retrieved for further review. Studies meeting the inclusion criteria will be assessed on methodological quality and the data will be extracted. Separate quantitative and qualitative analysis and synthesis will be performed and an overall analysis will be presented. Systematic review registration number: PROSPERO CRD42019137834