Limited guidelines inform the transition from paediatric to adult healthcare for youth and young adults (YYA) with eating disorders (EDs). This study will develop, implement, and evaluate Canadian Clinical Practice Guidelines for ED transition, including identifying the relevant measurement and evaluation tools for transition readiness and continuity of care. This study consists of three phases. Phase 1 involves conducting a scoping review of the evidence on transition interventions, outcomes, and measurement tools for YYA with EDs, along with guideline development using the modified Delphi method. Phase 2 identifies the contextual/cultural factors relevant to guideline implementation and co-designing an implementation protocol with governance committees and research partners. Phase 3 involves the application and evaluation of the proposed guide lines using the implementation protocol, and assessing the acceptability and feasibility of a prototype transition intervention in two Canadian paediatric ED programs. Results will provide the knowledge needed to enhance the lives of YYA, improve the effectiveness of the ED care system, and support the scale of the transition guidelines across Canada. These guidelines will have international relevance by potentially informing the field on how to support young people with EDs transitioning in similar funding structures and systems of care.