In the period of 3--16 June 1979, a satellite-tracked, free-drifting buoy passed through a Gulf Stream frontal perturbation and was entrained into a warm filament on the shoreward side of the perturbation. Significant speed convergence was noted as the buoy passed through the perturbation and approached the counterclockwise turn into the warm filament. In the warm filament, the buoy drifted to the southwest at speeds of about 0.1 to 0.3 m/sec. Eventually, the buoy drifted out of the filament and went westward in an apparent response to wind-induced surface drift.