In-field experiments with two autonomous kayaks demonstrating the ability to mission-interupt and intercept and follow another moving vehicle. Vehicle 1 on the left, is executing a "sentry" mission by keeping course around a set of way-points. (Each grid is 50 meters on each side). When a contact comes in range, the first vehicle interupts is mission and follows the contact. "Sensing" of the contact is done by each vehicle continuously broadcasting its position over 802.11b. This experiment was designed to test the interuptability of the the control architecture, and to verify a basic trailing behavior.