This article describes the study protocol for an evaluation of an innovative model of care that supports home health nurses (HHN) who serve children with medical complexity ( CMC). CMC constitute a small proportion of children, but have very high need for health services, are hospitalized frequently, and account for significant proportion of pediatric healthcare expenditures. High-quality home health nursing services are important for CMC, but models of care of home healthcare, after discharge of CMC from the hospital, have not been tested. Our project aims are to develop, implement, and test a model of care, called ICollab, to improve home healthcare delivery for CMC. The ICollab model consists of collaboration between HHN, primary-care physicians and clinicians of the complex care program of a tertiary-care children's hospital in the care of CMC. In this randomized clinical trial, we will recruit 110 CMC discharged home on home health nursing services. The intervention group (n = 55) will receive the ICollab intervention for 6 months post-discharge from the hospital, in addition to usual care. Children in the control group (n = 55) will receive only usual care. Outcome measures will include healthcare utilization metrics (hospitalization rates, emergency room visit rates, and days to readmission), caregiver burden and caregiver satisfaction with home healthcare, HHN retention, and HHN collaboration with other healthcare providers. We hypothesize that ICollab will reduce healthcare utilization and caregiver burden, and improve caregiver satisfaction with home healthcare, increase HHN retention, and increase HHN collaboration with other healthcare providers. Results of this study have the potential to provide a critically needed evidence-base for interventions to improve the quality of healthcare delivery for CMC. This study is registered on clinicaltrials.gov (NCT03978468) and is ongoing., Highlights • Although an increasing number of children with medical complexity in the U.S. receive home health nursing services, the quality of these services is not optimal. • Models of care that optimize communication and collaboration between home health nurses and other providers as children transition from hospital to home, have not been previously tested. • This RCT will evaluate the effect of an innovative care model on reducing hospital re-admissions, emergency room visits, improving caregiver satisfaction, reducing caregiver burden and improving home health nurse retention.