While treatments of neurological diseases have progressed remarkably well in the relative absence of detailed knowledge of either the mechanisms of diseases or the mechanisms of action of treatments, knowledge of both of these inter-dependent mechanisms will lead to new treatments with improved safety and the effectiveness. We aim to understand how the brain and spinal cord work together to ensure that the intended movement accomplishes the task at hand. Furthermore, we study how these motor circuits are affected by neurological conditions, with the aim of developing strategies so that the function of these circuits can be restored so as to improve quality of life. We combine electrophysiological and imaging techniques with mouse genetics to understand motor circuits, with a goal of developing new strategies to improve movement in neurological disease or following injury.