Introduction The Enhanced Recovery After Surgery programme (ERAS) is an approach to the perioperative care of patients encompassing multiple interventions and involving a wide range of different actors. It can thus be defined as a complex intervention. Despite the strength of the evidence-base in its support, the implementation of ERAS has been slow. This paper specifically explores the utility of Normalization Process Theory (NPT) as a methodological framework to aid exploration of ERAS implementation, with a focus on the core NPT construct coherence. Methods and materials The study employed qualitative methods guided by NPT. Semi-structured interviews were conducted with twenty-six healthcare professionals working in three specialities (thoracic, colorectal, head and neck) in a UK hospital. Data were analysed using an adapted Framework Approach. Results Coherence, or sense-making work, was key to successful implementation and demonstrated in the importance of participants believing in ERAS both as an individual and as a team. In order to invest in ERAS individuals needed to be able to differentiate its practices favourably with those enacted pre-implementation (differentiation). Participants also needed to understand their specific tasks and responsibilities (individual specification) and build a shared understanding (communal specification), resolving differences in planning meetings. Belief in the worth of ERAS was often aligned to evidence for its effectiveness or benefit to patients (internalization), so implementing ERAS therefore ‘made sense’. Sense-making work had strong links with aspects of implementation related to other NPT constructs including resource issues such as funding for data collection and feedback (reflexive monitoring: systemization) and failure to replace key staff members (collective action: skill set workability). Conclusions NPT was found to be a valuable heuristic device to employ in the exploration of ERAS implementation processes. NPT was useful in facilitating recognition of the importance of coherence work to successful implementation. However despite participants’ strong beliefs in the worth of ERAS, it was in translating these beliefs into action that barriers were encountered, highlighting the interconnectedness of NPT constructs and the complicated nature of implementing complex interventions.