Functional decline in older adults can lead to an increased need of assistance or even moving to a nursing home. Utilising home automation, power and wearable sensors, the system developed by the author continuously keeps track of the functional status of older adults through monitoring their daily life and allows health care professionals to create individualised rehabilitation programmes based on the changes in the older adult functional capacity and performance in daily life. The system uses the taxonomy of the International Classification of Functioning, Disability and Health (ICF) by the World Health Organization (WHO). It links sensor data to fve ICF items from three ICF categories and measures their change over time. The system successfully passed the first pre-clinical validation step on the real-world data of the OTAGO study, a 10-month randomised pilot intervention study with 20 (pre-)frail older adults (aged ≥ 75 years). Since this research is in an early stage further clinical studies are needed to fully validate the system.