Advances in brain science point to multiple risk factors for many childhood developmental disorders. These disorders have major impact both on children affected and on family well-being. Caregivers experience considerable stress and reduced self-efficacy through their child’s condition. They describe their experience with care systems as a confusing maze – contrary to accepted principles of family centeredness and continuity of care. In turn, poor family well-being interferes with healthy child development. The Family Navigator (FN) model of care responds to this unmet need for family empowerment in navigating complex systems; healthcare providers work with families as partners, sharing a common vision and goals. In other conditions, this model demonstrated improved care and health outcomes.In developing and evaluating the FN as a health systems role, we adopt a life-span perspective, focusing on transition periods that are carefully characterized in these populations: initial concerns, diagnosis, school entry, youth. In each transition period, affected families experience significant uncertainty and serious barriers in accessing care. The cascade of barriers has increasingly negative consequences for the individual and augments the life-time costs of their care. The FN is a preventative model. We enhance family resilience and empower caregivers, promoting optimal outcomes and reducing long-term burden of care for affected families and, ultimately, greater costs to society.FN model evaluation will be implemented within an Integrated University Health and Social Services Centre (CIUSS-Montreal West; Fig 1), grouping 47 points of service (primary to specialist) for 38% of the Montreal territory. We also engage a global network with multidisciplinary expertise, cross-sector experience and global reach in achieving two Aims:(1) Measure efficacy of the Family NavigatorThe FN is a non-specialist who collaborates with families to support caregiver–child interactions, offer relevant and tailored information about child health and services, and maintain a responsive relationship with the family. Navigators apply flexible problem-solving to overcome real or perceived barriers to care. We will evaluate this model in a randomized controlled trial (RCT) implemented directly within the CIUSS-Montreal West. The target group are caregivers of children in any key transition periods from infancy to youth.(2) Assess impact on families and health systemsNavigation models are complex interventions that succeed if they empower affected families and promote greater care continuity. Therefore, we rely on complementary methods to inform future delivery and sustainability. We will capture perspectives of children and youth with neurodevelopmental disorders and their families, examining the meaning to them of ‘good outcomes’. We will also evaluate cost and implementation issues related to integrating the FN into routine health system services.Knowledge we generate will be readily available to multiple decision makers. Locally, our data will be shared with our partner (TAU) who will conduct an independent cost-effectiveness analysis and issue policy recommendations relevant to Quebec. Globally, we are members of a global network launched by the WHO to implement similar programs in 15 countries, with whom we will exchange knowledge. The FN addresses global priorities by generating critical knowledge to promote caregiver empowerment and care continuity.