Effects of sodium dodecyl sulfate (SDS) on surface tension and rheology of aqueous solutions of an associative polymer, poly(ethylene oxide)-b-poly(propylene oxide)-b-(poly(ethylene oxide))-g-poly(acrylic acid) (Pluronic-PAA) have been studied. SDS starts to bind to the Pluronic-PAA copolymer at a concentration that is 25-fold lower than the critical micellization concentration (CMC) of the surfactant. The data indicate predominant binding between SDS and polyether segments of Pluronic-PAA. Incorporation of SDS into the Plutonic micelles makes the polymer less surface-active, as the surface tension increases. The Pluronic-PAA chains collapse when SDS binds, because the surfactant enhances hydrophobic intramolecular associations.