This paper presents two case studies, which highlight the practical work involved in developing and deploying dependable healthcare systems. It shows how dependability is a thoroughgoingly practical, contexted achievement. We show how dependability is an outcome of the reasoning and argumentation processes that stakeholders engage in, in situations such as design and testing. What becomes relevant during these interactions stands as the dependability criteria that must be achieved. Furthermore, we examine the way in which different dependability criteria need to be managed, and even relatively prioritised, before finally discussing the types of work this provokes at the boundaries of organisations, particularly when integrating work and technologies.