An actuation method for a surgical tool and the tool itself, which includes a proximal coupling portion from which two hydraulically actuatable, pivotably connected members extend. Each of the branches, at least at their distal ends, have an active portion and form in the coupling portion a boundary for at least part of a fluid-tight, fluid-fillable cavity. A pivot position of the members and a volume of the fluid in the cavity are operatively coupled with one another. An actuation method for a micro-surgical tool and the micro-surgical tool, which includes a proximal handle with an actuation device and a distally disposed inventive hydraulically actuatable surgical tool, which is connected by a shaft with the handle and can be actuated by the actuation device.