The present invention describes a method and an apparatus for surface strengthening and/or smoothing of an integrally bladed rotor area of a jet engine. The rotor area can be connected to a device and held by the latter inside the container in a position equivalent to an at least approximately horizontal orientation of a rotary axis of the rotor area. A space delimited by the container and the rotor area between a surface of the rotor area and that surface of the container facing the rotor area is filled at least partially with strengthening and/or smoothing elements. A relative movement is generated between the surface of the rotor area and the strengthening and/or smoothing elements. The surface region of the rotor area to be strengthened and/or smoothed is at a distance from the surface of the container facing the rotor area.