The emerging pervasive computing is regarded as a promising solution to the systems of personal healthcare and emergency aid, which can monitor personal health status in a real-time manner and automatically issue the alert for medical aids in case of emergency. However, the implementation of such a system is not trivial due to the issues, including 1) the system operations without complicated caregiver aid to reduce cost of human resource, 2) vital sensor deployment for user comfort, 3) on-site vital data process and storage for energy saving in data transmission, and 4) timely communication with healthcare centre for reporting users’ health status and seeking urgent medical aids. In this paper, we propose a novel wearable personal healthcare and emergency aid system, namely WAITER. Our system does not require specific caregiver aid. WAITER just employs the tiny wearable sensors to continuously collect user’s vital signals and Bluetooth device to transmit the sensory data to a mob...