"exert discipline" is correct and usable in written English.
You can use it when referring to the imposition of standards or rules of behavior to guide one's actions. For example, "The coach works hard to exert discipline and focus on his team before the big game."
Blair added, "She keeps trying to shape things up, knows what's wrong, but he can't fire people, exert discipline, punish leakers".
It is no laughing matter for Chelsea, however, who stand accused of failing to exert discipline over their star-studded dressing room.
Without that fear, he said, unsecured creditors will not exert discipline on the banks by monitoring their risk-taking and pricing their loans appropriately.
It may be years before deregulated providers of higher education exert discipline over the old-timers, but it is a start.
But the bigger point is that financial markets are quite able to exert discipline, even over euro members: witness the credit downgrade suffered by Italy last year.
But without a producer to exert discipline, the Duke Nukem team were free to fiddle for as long as they wished.
In a letter to Senators Feinstein and Snowe, who introduced a carbon market governance bill, the International Emissions Trading Association asserted that 'the market itself recognizes the importance of integrity and exerts discipline on participants,'" citing a number of self-policing tactics.
But when loyalty extends to condoning malpractice and crime, fear can still exert its discipline.
"The problem is, who could exert the discipline to keep people to live up to their bargains?" he said.
Yet Mr Vickers frets that European courts may not exert enough discipline on the commission's future actions in this area.
"That would end any incentive for countries to exert budgetary discipline if it's clear that a handful of countries guarantee everything and are liable".
