The research plan will lead to the development of tools and principles to help explain how body oscillations contribute to the stability, speed, and efficiency of high-speed locomotion. The development of new dynamical models will help us understand how to design and control these motions in robots and how these motions should change as running changes from horizontal to vertical domains and will enable more dextrous and agile locomotion. Specific research objectives in support of these broader goals are: Identify how translational oscillations and roll, pitch, and yaw are coupled in running and what specific dynamic advantages these confer Characterize the changes in sagittal plane motions as the incline changes from horizontal to vertical Identify how rotations are coupled in high-speed climbing and how these affect attachment and performance Evaluate the effectiveness of the resulting dynamical models in improving the performance of running robots.