  We present a volumetric communication system that is designed for remote
assistance of procedural tasks. The system allows a remote expert to visually
guide a local operator. The two parties share a view that is spatially
identical, but for the local operator it is of the object on which they
operate, while for the remote expert, the object is presented as a mixed
reality "hologram". Guidance is provided by voice, gestures, and annotations
performed directly on the object of interest or its hologram. At each end of
the communication, spatial is visualized using mixed-reality glasses.
