To walk without pain or other problems is considered a priority for activities of daily life. To maintain or improve walking, many therapeutic solutions can be provided. But before making a therapeutic choice, it is necessary to identify and understand precisely a person's gait deviations. For this, medical teams generally use an instrumented test of walking that is called "Clinical Gait Analysis". Although this examination is recognized and has an undeniable contribution, it is still necessary to improve the process that leads to the choice of treatment to resolve gait deviations. These improvements have to focus on the protocols and the tools used to quantify and analyze gait deviations, knowledge of normal and pathological gait, and the knowledge of the effect of treatments on pathological gait.