Monitoring people during sleep time is of particular interest to patients with sleep disorders and elderly people or infants. We have developed a battery powered electronic system to monitor people in the bed, store the data and send them through a wireless link to a PC. The resulting data will be subject to further analysis using pattern recognition to evaluate the feasibility of using the system as an indicator of sleep quality. The system is able to detect presence on the bed and movements and breathing of the patient. The changes in pressure distribution on the mattress cause changes in pressure in the layers of the sensor and a voltage will appear on the electrodes. The detection ability depends strongly on the shape of the mattress and the bedbase.