Public sector organisations are challenged by the Carbon Reduction Commitment (CRC) to contribute to an 80% reduction of carbon emissions by 2050. Due to the size of these organisations, even changes which are small in percentage terms can lead to significant energy savings. Energy efficiency and energy demand reduction are recognised by the Department of Energy and Climate Change (DECC)[1] to not only involve technological change, but also complex interrelations between the buildings, their systems and controls, and their users. In comparison to individual households, interactions in non-domestic buildings are complicated, due to the complex nature of the organisations that inhabit them. Three levels of analysis are evident in the context of organisations: i) institutional structures, rules, and policies; ii) the social and behavioural characteristics of the organisation; and iii) individual behaviours in the context of the organisation [2]. Changes in energy use can be enabled or hindered at each of these levels. This paper presents the current work of the Enhance research project, which takes a multidisciplinary approach to the study of energy use, and the potential for energy saving through smart digital feedback in two public sector organisations: a University, and a City Council in the UK. The project has a multidisciplinary team with expertise in data analytics, architecture and social sciences, enabling the study of complex interactions of infrastructure, organisations and users. The Enhance project is engaging in a living lab methodology to embrace its holistic approach to understanding energy use in the non-domestic buildings, and uses both quantitative and qualitative data gathering, analysis and feedback. We conclude that utilising the living lab methodology for exploring energy issues in large organisations involves gaining and understanding of formal and practical roles of individuals at multiple levels of the organisation, and flexibility in which roles and levels need to be involved in the living lab over time.