The Model of Engaging Communities Collaboratively was developed with the integration of literature reviews in cultural adaptation approaches, engagement and implementation approaches; and international Indigenous feedback to inform the processes of implementing evidence-based practices (EBP) with Indigenous populations. This model synthesises the collective strengths of these approaches and feedback and provides checklists for practicality of use by researchers, service providers and global Indigenous populations alike. This article describes the process of the theoretical development of the MECC and the feedback that refined it into a functional model for working with Indigenous populations worldwide.