A monitoring system is disclosed. The system comprises a range detection system, configured for scanning a scene to provide range data arranged gridwise over a plurality of picture elements, and a data processing system configured for processing the range data to monitor hygienic activity, preferably hand hygienic activity, of an individual in the scene. Preferably, the picture elements are devoid of any color data and any grayscale data. In some embodiments of the present invention the data processing system identifies one or more of the moments for hand hygiene as defined by the World Health Organization, and monitors the hygienic activity in relation to these five moments.