Usually just called missions, these form the backbone of the storyline in each campaign.

A mission of such magnitude, scheduled for launching next Monday, calls attention to how far space flight has advanced in its first 40 years.

That was being overly careful, but tonight's mission called for it.

Instead, its mission calls for a steady effort to educate the rest of the world about the human rights issue in China.

And that was exactly what this mission called for.

His mission didn't call for indiscriminate assault on anything that moved.

Different missions call for different tools so what to take is crucial.

But another mission calls him on a journey leading into the past.

The mission called for no eyewitnesses to the war here.

You vaunt the 17 military missions carried out and call for more.