PolyU recently kicked off the Jockey Club Smart City Tree Management Project that seeks to apply smart sensing technology (SST) and Geographic Information Systems (GIS) for monitoring tree stability to enhance timely appropriate mitigation measures for sustaining longer tree lives in Hong Kong. This pilot project will tailor-make and install sensors on the lower trunk of selected urban trees to monitor their tilting angle in a 3-dimensional manner, as a way of assessing the stability of the root and thus the tree. Data will be collected for a quantifiable analysis of the trees’ root plate movement through the use of SST. It will provide scientific data to supplement the existing tree preservation mechanism through early notification and response, aiming to contribute towards sustaining the invaluable urban trees in the city.