By small-angle neutron scattering experiments at a concentration of c = 105.3 mM/dm(3), a decrease of the size of tetradecyltrimethylammonium bromide micelles (C14H29N(CH3)(3)Br-+(-)) in aqueous solutions as a function of increasing temperature was observed. It seems that the shape of the micelles is not, as usually assumed, spherical but is slightly anisometric.