Well-established theoretical models and methods are available for evaluating the implementation and sustainability of complex healthcare interventions, including widespread recognition of the importance of accounting for context-intervention-outcome interactions within such investigations. However, there is a need to translate conceptualisations of context into analytical tools which enable the dynamic relationship between context and intervention implementation to be captured and understood. In this seminar, I will draw on theoretical perspectives associated with Linguistic Ethnography (LE), which provides theoretical and methodological tools for a close investigation of social action in context. Using LE, I will propose an alternative approach to the investigation of intervention delivery within context, through a consideration of texts, distributed and enacted at multiple contextual levels. Using audio and video data, I will discuss the enactment of different texts, (algorithms within a computer decision support software and a set of clinical guidelines), from two studies involving primary care nurse consultations: the ESTEEM trial – a cluster randomised controlled trial of primary care telephone triage; and PACK Child – a feasibility study of paediatric primary care in South Africa. I will examine staff orientation to standardised, or ‘fixed’, texts at the point of intervention delivery to illustrate how such observations are not solely premised on identifying routines or practices of implementation, but where ‘interventions as intended’ are disrupted, or break down. In doing so, I consider what can be gained from tracking the circulation of different texts across different levels of context, including how we might expose the ‘active ingredients’ of interventions to empirical observation.