An active damper system is provided for a vehicle, in particular a motor vehicle. It includes a damper unit with a cylinder, a piston which is guided in the cylinder, and a piston rod which is connected to the piston. The piston divides the cylinder into a first chamber and a second chamber, and the damper unit is designed to be arranged between a body and a wheel of the vehicle. The damper system also has a pump for changing the pressure in the two chambers and for moving the piston, a first valve, a second valve, which is connected to the first valve in series, a third valve, and a fourth valve, which is connected to the third valve in series. The first and second valve are connected in parallel to the third and fourth valve. A fluid-conductive first line leads to the first chamber between the first valve and the second valve, and a fluid-conductive second line leads to the second chamber between the third valve and the fourth valve. A low-pressure side of the pump is connected between the first valve and the fourth valve, and a pressure side of the pump is connected between the second valve and the third valve. The first valve, the second valve, the third valve, and the fourth valve can be switched in order to selectively block and release the flow of fluid. A control unit is provided for switching the four valves such that the pump rotates in the same direction when compressing and rebounding during an electromotor operation and a generator operation.