Cocamidopropyl betaine makes products feel creamier. It's a thickening agent that adds viscosity to products. This makes them feel richer and makes them less likely to drip while you use them. Used as a foam booster in shampoos. It is a medium-strength surfactant also used in bath products like hand soaps. It is also used in cosmetics as an emulsifying agent and thickener, and to reduce irritation purely ionic surfactants would cause.