Schools have the potential to support children's learning of nutritionrelated behaviours through their experiences with school food. The transformation of school meal programmes have featured within policies in the UK and the USA. However, such policies are at risk of not meeting their objectives as many children remain unwilling to consume healthier food. Socio-ecological health improvement frameworks emphasise the importance of assessing health needs and designing/evaluating policies by considering processes operating at policy, community, organisational and inter/intra-personal levels. This article explores the usefulness of the socioecological perspective as: a theoretical framework to assess health policy and needs; a methodological framework to inform the design of associated research; and an evaluative framework for policy implementations. This is achieved by demonstrating how a socio-ecological perspective was deployed during an exploratory study into the role of primary school dining halls in improving children's nutrition-related behaviour. This study revealed how policies at local and school levels reflected national objectives with respect to nutritional guidelines, but were also influenced by multiple, competing interests at other socio-ecological levels. These included pupils' food preferences; organisational objectives such as protecting school meal uptake; and the practices of school meal staff. It is argued that higher level policy interventions may have limited effectiveness if undermined by lack of attention to lower level factors. The use of socio-ecological frameworks as theoretical, methodological and evaluative tools to support a consistent, holistic approach during the design, implementation and evaluation of health improvement policies is recommended.