Relations between them and their royal masters were relations of mutual dependence, with the minister-favourite often gaining the upper hand.

ECONOMIST: Courtiers and counsellors

Moscow, though, has managed to turn this mutual dependence into one-sided leverage.

CENTERFORSECURITYPOLICY: A Bear energy market

"There is a level of mutual dependence - we depend on them for energy supplies and we are energy consumers for them, " he said.

BBC: EU concern at Russia human rights

The mutual dependence of PUCs and the industries they regulate explains why the prospect of losing out on a growing VoIP market sent California regulators into a tailspin.

FORBES: The Madness of Regulating VoIP as a Public Utility

They wrongly equated mutual dependence with unilateral leverage.

ECONOMIST: Banyan

One issue everyone agreed upon was a "mutual desire to reduce our dependence on imported oil, " Bush said.

FORBES: Detroit Seeks White House Help