The novelty of performance upon command soon wore off.

It was a one year course for senior enlisted personnel which concentrated upon command and administration.

Support weapons can also be called down upon command, but, like other units, must load up first.

There was no direct vision, only a series of screens revealing upon command what lay outside.

He made a stick that bursts into flame upon command?

It is ready to be carried out upon command, at which time it becomes known as an operational order.

Then upon command the troopers moved forward cautiously and surrounded them.

Upon command, the computer dials the telephone number to be called.

You come here upon command, and for a specific purpose.

They assume any form, significance or quality upon command.