A method has been developed of preventing or limiting formation of adhesions by administering to a site in need thereof, in the absence of or after bleeding or leakage of fluid has been substantially stopped, a self-assembling material which forms a barrier to formation of adhesions. In certain embodiments, the self assembling materials are peptidomimetics, nucleotidomimetics, di- and triblock copolymers, N-alkylacrylamides, or dendrimers. These materials are also useful in a method for regeneration or repair of tissue or cells forming tissue.