Mindful care is an approach to caregiving that has been observed following staff mindfulness training. While it has been associated with benefits to both the caregiver and the care recipient, the observable behavioural correlates of mindful caregiving remain largely unspecified. The purpose of this study was to identify observable mindful care behaviours and develop a behavioural marker system that can be used to measure them. Eight subject matter experts were interviewed, and a template analysis was carried out on the resulting interview transcripts. In total, 33 observable mindful care behaviours were generated and organized according to a hierarchical framework with two major themes: 1) Attention to immediate experience; and 2) Orientation to challenging experiences. Interviews were recoded using the framework, and adjustments were made until an acceptable level of interrater reliability was achieved. Member checks confirmed the appropriateness of the behaviours that were identified. The behaviours were then modified for use in a behavioural marker system for mindful care, which utilizes momentary time sampling and partial interval recording strategies. The resulting behavioural marker system will not only contribute to the evaluation of caregiver mindfulness training programs but will also promote better caregiving and better quality of life for care recipients.