Medical device software is a risky business. Failure of the software can have potentially catastrophic effects, leading to injury of patients or even death. It is therefore no surprise that regulators throughout the world are penalising medical device manufacturers that do not demonstrate that sufficient attention is devoted to the areas of hazard analysis and risk management (RM) throughout the software lifecycle. If a medical device company fails to comply with the regulations of a given country, in effect they surrender their legal right to market their device in that country. With so much at stake, it is in everybody's best interest that the medical device manufacturer gets it right. However, with so many different standards, regulatory guidance papers and industry guides on RM, the task of collating this information into a usable model is itself daunting. This paper seeks to extract the important concepts from a number of industry accepted standards and guides, and present them as a generic usable model for the medical device software industry. © 2006 ACM.