Prolab's Glucosamine Chondroitin MSM is an effective combination of ingredients to help promote and maintain healthy joints and connective tissue. MSM is a natural source of sulfur that is essential for the healthy function and structure of joints. Chondroitin helps lubricate joints and cartlidge as well as improve this lubricating fluid's thickness and elasticity. Glucosamine aids in the rebuilding and repairing of cartliage in addition to being a component for the development of strong connective tissue.