Nokia Sentry is a wearable system that detects stress using a heart-rate sensor, an Android smartphone, and cloud computing. Sentry notifies authorities and activates body cameras when a wearer, such as a police officer, encounters stress. The current rendition of Sentry suffers from two deficiencies: it relies solely on heart-rate measurements, and it only detects stress using a broad stress threshold that does not account for an individual wearer’s unique stress response. To enhance Sentry, we design a wearable sensor network and an accompanying cloud software architecture that constructs a wearer’s personalized stress response profile. In a typical use-case, our multi-sensor design characterizes a wearer’s stress response as they undergo physical and mental assessments.