Sober Steering is developing a wearable alcohol sensor system that communicates with a vehicle to prevent drunk driving. The FitBit-style wearable device will communicate wirelessly with a Sober Steering module located behind the dash of the vehicle to provide interlock functionality and instant alerts. The wearable alcohol sensor system will be monitored and controlled by a smart phone app (ideally controlled by parents or fleet vehicle dispatch). The proposed project aims to further develop sensors capable of providing alcohol sensing functionality for the wearable device.