This paper describes two case studies using a 5-step protocol to determine functional space requirements for cardiac and neonatal intensive care clinical activities. Functional space experiments were conducted to determine the spatial requirements (defined as the minimumsized rectangle to encompass the Link Analysis). The data were collected with multi-directional filming and analysed frame-by-frame to plot the movements between the nurses and other components in the space. The average clinical functional space for the adult critical care unit was 22.83m2 (excluding family and hygiene space and in-room storage). The average functional clinical space for neonatal intensive care unit was 13.5m2 (excluding circulation and storage). The use of the 5-step protocol is reviewed, with limitations in case study 1 addressed in case study 2. The findings from both case studies have been incorporated into government guidance and achieved knowledge transfer by being implemented in building design.