The invention relates to an instrument for surgery, in particular minimally invasive surgery. The instrument includes means for feeding back a force which is exerted on the working element of the instrument to the operating element. These means include at least a first force sensor for measuring the force which is exerted on the working element, a control unit and a first actuator. On the basis of a signal which originates from the first force sensor, the control unit controls at least the first actuator in order to control the operating element. Furthermore, the means preferably include a first position sensor for measuring a position of the working element with respect to the frame. The control unit advantageously determines an impedance which the working element is subject to as a result of the presence of a tissue or the like, on the basis of which impedance the control unit controls at least the first actuator.