Thermage treatment is the means of using radiofrequency technology, called RF, to help heat the internal layers of the skin in order to stimulate the body's production of collagen. The process is safe and there is no damage to the outer layer of skin because the outer surface is kept cool. However, the deep heating of this treatment focuses on the collagen in the dermis (the middle layer of the skin) and the subcutaneous tissue, the deep layer of the skin. By stimulating the body to produce more collagen here, the outer skin is improved with tighter, smoother skin that looks youthful.