Disclosed are personal care or cosmetic compositions comprising a dicarboxy functionalized polyorganosiloxane and methods for the cleaning or the treatment of hair or skin and for enhancing delivery of active agents to hair or skin with the compositions. Said personal care or cosmetic compositions can be formulated in a wide variety of types of products for the skin and/or hair (or, more generally, keratin) such as mousses, gels (in particular hair dressing gels), conditioners, hair dressing formulations or to aid comb-through of hair, rinsing formulae, hand and body lotions, skin moisturizing products, skin cleansing or disinfecting compositions, shower gels, toilet milks, cream foundations, make-up removal compositions, sun and ultraviolet radiation protection lotions, creams or gels, skin care creams, anti-age preparations, anti-acne preparations, local analgesics, mascaras, deodorants, antiperspirants, lipsticks and other compositions of the same type. The use of dicarboxy functionalized polyorganosiloxanes permits to confer benefits such as an increase in shine, gloss or volume of hair, easier comb-through of hair, easier spreadability or slipperiness onto skin; it also permits a better persistence of active materials or benefits agents deposited onto the surface and consequently permits to maintain the activity of the composition deposited on the surface over time. The dicarboxy functionalized polyorganosiloxane can be used in an amount of from about 0.1% to about 30%, preferably from about 3% to about 10% by weight, of said personal care or cosmetic compositions.