Big gaps can form between what clients have and what they owe, and these temporary imbalances pose risks. Even if these imbalances arise and are resolved in the normal course of business (and thus seem innocuous), they can still do harm. For one thing, discrepancies introduce delays in rec-ognizing exposures, but equally important, they create opportunities for clever and unscrupulous employees to figure out how to take advantage of the permissive treatment of temporary imbalances. Nick Leeson was certainlyboth clever and unscrupulous.