This paper describes a novel approach to the unobtrusive assessment of a subset of gait characteristics using a light detection and ranging (LIDAR) device. The developed device is poised to enable unobtrusive, nearly continuous monitoring and inference of patients' gait characteristics to assess physical and cognitive states. The device provides a rapidly sampled signal representing the distance of a participant's body from the LIDAR device. The densely sampled distance estimation is processed by custom algorithms that can potentially be used to estimate various gait characteristics such as step size, cadence, double support, and even step-size symmetry.Clinical Relevance- Since gait is a complex behavior that requires seamless cooperation of multiple systems, including sensation, perception, muscular synergies, and even cognition. Subtle changes in gait may, therefore, indicate issues with physical and mental functionality. In addition to the walking speed, the gait monitoring results can provide inferences about the physical and cognitive states of the unobtrusively monitored individuals using their own data as a baseline.