The literature regarding implementation science of evidence-based health interventions in Maori communities is limited, and there is a push for new and innovative delivery methods of health interventions in New Zealand. The purpose of the study was to identify the facilitators and barriers in implementing a health intervention designed by others and was framed by the Consolidated Framework for Implementation Research (CFIR). This study explored general perceptions of the implementation process and also included a case study, the Kaumatua Mana Motuhake (older people's autonomy and self-actualization) project; a codesigned peer education intervention for older Maori. Semistructured interviews (N = 17) were conducted via face-to-face, phone, or Zoom with health and social service professionals with experience working with Maori communities. Thematic analysis was used to analyze the data. The facilitators included community engagement, program structure, program adaptability and creators' experience. The barriers consisted of funding access, funding constraints and organizational constraints. The findings support key elements within the CFIR, highlighting the importance of community engagement and adaptability. Additionally, this study identified nuanced aspects of funding and resources that constrain organisations in employing health interventions designed by others.