This chapter discusses the purposes, functions and roles of skin care cosmetics such as face cleansing cosmetics, lotions, milky lotions, creams, gels, essences (beauty lotions), packs and masks, shaving cosmetics, and several other products (for example, powder and cleansing oil). The purposes of skin care cosmetics include cleaning the skin, preserve the skin's moisture balance, stimulate skin metabolism, and protect the skin from harmful ultraviolet radiation. Skin care cosmetics contain substances which enable the skin to function properly. They support its homeostasis function so that it is maintained in a beautiful and healthy condition or regains such a state if it is not. The basic functions include cleansing, anti-drying, ultraviolet damage prevention, antioxidation and invigoration but they can also clear up skin problems, have a whitening effect to combat skin aging-associated troubles (liver spots and freckles due to the sun's rays), prevent wrinkles, sagging skin and acne. The roles played by skin care cosmetics include maintaining homeostasis in the skin and restore it if it has been lost (keep the skin healthy and beautiful), delay aging in the skin, and provide a solution to skin problems. They must also be safe when used constantly over long periods.