We describe a method for simultaneously recovering the trajectory of a target and the external calibration parameters of non-overlapping cameras in a multi-camera system. Each camera is assumed to measure the location of a moving target within its field of view with respect to the camera?s ground-plane coordinate system. Calibrating the network of cameras requires aligning each camera?s ground-plane coordinate system with a global ground-plane coordinate system. Prior knowledge about the target?s dynamics can compensate for the lack of overlap between the camera fields of view. The target is allowed to move freely with varying speed and direction. We demonstrate the idea with a network of indoor wireless cameras.