Abstract: Flavor oscillations of B0-anti-B0 mesons have been studied in e+e- annihilation data collected with the BaBar detector at center-of-mass energies near the Upsilon(4S) resonance. The event sample consists of one neutral B meson reconstructed in a hadronic mode, while the flavor of the recoiling B meson in the event is determined with a tagging algorithm that uses the relation between the flavor of the b quark and the charges of its decay products. By simultaneously fitting the time dependence of the mixed and unmixed final states, the oscillation frequency is determined.