Background Restaurant food waste remains a significant sustainability challenge, yet existing research has largely examined food waste determinants, interventions, and management practices in isolation. This systematic mapping review synthesises evidence from 68 studies to examine how restaurant characteristics, organisational capabilities, interventions, and macro-environmental conditions interact to shape restaurant food waste outcomes. Drawing on an Applied Systems Theory perspective and a PESTLE + G analytical framework, the review develops a systems-based framework for understanding restaurant food waste management. Key findings and conclusions The analysis suggests that FW outcomes emerge through interactions between restaurant characteristics, organisational capabilities, and external contextual influences rather than from isolated interventions. Organisational capabilities, including managerial commitment, staff training, forecasting capacity, and measurement practices, emerged as a key linking construct connecting environmental conditions with operational responses. Three recurring pathways (policy, resource, and behavioural) were identified, alongside five leverage points through which FW reduction may be most effectively targeted: policy and regulation, technology-enabled decision support, organisational capability development, measurement and organisational learning, and customer engagement. A central insight of the review is that similar interventions may generate different outcomes across restaurant contexts because they are implemented within different organisational and environmental systems.The review contributes a systems-oriented framework for aligning FW interventions with organisational and contextual conditions. Future research should examine framework transferability across different cultural and institutional settings, alongside the role of emerging technologies and organisational learning in shaping FW outcomes. Findings should be interpreted in light of the review's geographical scope and the absence of formal comparative effect-size synthesis.
