Ethnography has been introduced into technology design lifecycles to help sensitise new technologies to the work practices of their intended users. This paper reports on how ethnography was used in parallel to technology prototyping in the design of a workflow system to improve accuracy and efficiency in banking in India. Unlike previously largely positive reports of how ethnography helps to shape design, the case study presented here highlights the difficulty of conducting ethnography in parallel to prototype development. The tight contingencies of the prototyping cycle meant that only some of the ethnographic findings were incorporated into the design – those that fitted easily with the envisaged prototype. However, the findings from the ethnography suggested more fundamental changes were required. In this case, there was no way to incorporate such changes. We discuss the impact of this on the solution and lessons drawn for future interventions.