A comparative approach for the use of mesenchymal stromal cells (MSCs) in the treatment of joint diseases is being undertaken. Since horses can be very high level athletes, like some human beings, they could benefit from treatment with MSCs, but also serve as a model for the evaluation of such a treatment. In both species of horses and humans, when a joint disorder occurs, an inflammation of the environment develops, which is self-sustaining and aggravates the initial disorder. The fight against local inflammation is therefore of primary importance and is partially taken care of by the MSCs, which also have immuno-modulating and trophic functions. In order to make progress on the therapeutic applications of MSCs, in both humans and horses, multidisciplinary collaboration is essential and the clinician?s skills are required to precisely locate an early joint disease requiring treatment with MSCs, keeping in mind that an early and multimodal approach to the disease is probably more effective.