Census® wrist tags and readers have been deployed within a number of Spanish care homes to monitor and control the movements of geriatric patents suffering from Alzheimer's and/or dementia. The readers can be set to raise an alarm should a patient tag be detected in isolation. Alternatively the relay can be used to activate the door lock so the individual cannot wander outside the safe area alone. If a “carers” tag is detected simultaneously with a patient tag the alarm is suppressed. The same solution has been applied in the UK in facilities caring for autistic children.