Technology design is a complex task, and acceptability is enhanced when usability is central to its design. Evaluating usability is a challenge for purchasers and developers of technology. We have developed a framework for testing the usability of clinical monitoring technology through literature review and experience designing clinical monitors. The framework can help designers meet key international usability norms. The framework includes these direct testing methods: thinking aloud, question asking, co-discovery, performance and psychophysiological measurement. Indirect testing methods include: questionnaires and interviews, observation and ethnographic studies, and self-reporting logs. Inspection, a third usability testing method, is also included. The use of these methods is described and practical examples of how they would be used in the development of an innovative monitor are given throughout. This framework is built on a range of methods to ensure harmony between users and new clinical monitoring technology, and have been selected to be practical to use.