Background <p>Advocacy is a key professional responsibility of nurses. Yet, there is a dearth of frameworks grounded in nursing practice that articulate this role, particularly in driving sustainable change.</p> Aim <p>This study aimed to describe the diverse forms and strategies used in nurse-led advocacy, to develop a conceptual framework for fostering sustainable healthcare practices and nurse-led change from the bedside to the system-level.</p> Method <p>A descriptive qualitative design was used to describe how nurse-led advocacy is manifested in the stories of RCN-UK ‘Nurse of the Year’ 2016–2023 awardees. The Framework Method was applied to analyse seven publicly available nurse-led advocacy initiatives. The analysis involved familiarisation, identification of a thematic framework, indexing, charting, mapping and interpretation to synthesise key advocacy dimensions.</p> Findings <p>The analysis resulted in the development of the TRIL Nurse Advocacy Model. This novel thematic framework posits that nurse-led advocacy comprises three interconnected pillars: Transformative Action, Relational Co-design and Institutional Legacy. Transformative action highlights the nurses’ capacity for crisis-responsive innovations, people-centred transformations, advancing health equity, and revisioning practice standards. Relational Co-design underscores the importance of cross-sector partnership, community-led empowerment, and workforce inspiration. Institutional Legacy emphasises the critical role of policy and resource formalisation, and sustainable system integration in ensuring lasting impact. The model also recognises the reality of the context of barriers, which underscores the need for strategic navigation to overcome systemic resistance, thereby creating sustainable healthcare.</p> Conclusion <p>The TRIL Nurse Advocacy Model provides a comprehensive lens for advancing nurse-led advocacy. It offers significant implications for nursing education by guiding curriculum development to cultivate advocacy skills. It also impacts policy by highlighting the contributions of nurses to systemic change, and in practice, by empowering nurses to strategically plan and evaluate their initiatives toward building resilient and sustainable healthcare systems.</p> Clinic trail number <p>Not applicable</p>