[InterceptPoint]

I understand where they will get volunteers for the HEAD PART. But the BODY PART will require something more than just volunteers.

[Red Badger]

ISIS don't need no steenking volunteers!............

[a fool in paradise]

They should first master keeping the severed head alive (this has been done with dogs and other things, but it has not been done with humans).

[Ransomed]

40+ years ago Larry Niven speculated that once the technology made it feasible for the general public to extend their life this way they would eventually get their donor bodies by employing capital punishment for things like jaywalking and not wearing a seat belt while driving.

Freegards

[Boogieman]

They’ll get the bodies the same way they get hearts, lungs, kidneys, etc. Declare a non-responsive person “brain dead” and then harvest the parts they want while killing that person in the process.