These call for a minimum level of earnings at strategic intervals throughout the relationship.

Ms. Dean worked her stars hard, deploying them, like warheads, at strategic intervals as the film made its way across the country.

He wouldn't put it past the wily fox to have professional killers stationed at strategic intervals, but so far there had been no enemy action.

Then on the grounds themselves, I have them spotted all over at strategic intervals, wherever there's any cover.

Secret Service agents were stationed at strategic intervals, no doubt ensuring that the area was free of snipers and other potential malefactors.

She could see a dozen armed Haaar-kyut stationed at strategic intervals throughout the garden.

An essential part of Sinclair's marketing strategy was to use regular cost-cutting at strategic intervals to maintain market share.

Instructor boxes are distributed at strategic intervals throughout the manual.

The fence was overlooked by watchtowers located at strategic intervals along the border.

The whole place was well lit, both by silver moonlight and by lighting placed at strategic intervals.