Human-centred design is an approach to product development, that aims to make products usable by focusing on users and their needs, by applying human factors/ergonomics, and usability knowledge and techniques. Co-design is a method of working with users over the duration of the design process, to ensure there is an optimised fit between the user and an appropriate technology. However user centered design practices typically require considerable amounts of time. This paper describes how, under the right circumstances, co-design can be an effective product development strategy, even within restrictive time and resource constraints. A project to design and develop a nurse-call pendant (button) to meet the specific needs of residential aged-care was conducted using co-design strategies. The strategies employed were effective and vital to the success of the outcome, although the activities were highly constrained by time and available resources. This paper will explain how the co-design process was implemented and why it was successful under these circumstances.