This study aims to critically examine operational sustainability (OS) in English public universities, uniquely integrating neo-institutional and organisational legitimacy theories to explore the alignment of sustainability strategies with organisational practices. Adopting a rigorous qualitative approach, this study combines semi-structured interviews with 20 OS managers and a thorough document analysis involving over 800 documents. This robust methodology ensures a deep exploration of institutional sustainability dynamics. This study reveals a significant discrepancy between stated and actual sustainability performances, with institutions frequently engaging in symbolic sustainability efforts. It highlights the need for robust benchmarking systems to accurately measure and encourage genuine sustainability integration.

The identified barriers and the subsequent recommended approaches can guide public universities in their strategic planning and implementation of OS initiatives, ensuring more effective outcomes. This study underscores the importance of university stakeholders in shaping OS engagement. It signals a need for broader societal awareness and collaboration to truly drive universities towards a more sustainable future. This study is original in its dual-theoretical approach, applying both neo-institutional and organisational legitimacy theories to dissect the complexities of sustainability in higher education. It extends the discourse on sustainability by scrutinising the often-overlooked gap between policy and practice, providing a nuanced understanding of institutional behaviours and pressures.