Balance Sheet Management Group

They control the clearing accounts in various currencies. They are going to have accounts with the ECB, BOE, Fed, SNB, etc. They fund the banks activities. Every trade made on every desk is really a swap of some asset for another asset. In the case of a spot FX trade, you trade one currency for another. For cash equities, bonds, or commodities, you are swapping cash for the instrument you are interested in purchasing. In the case of options, you are swapping some cash for the right to buy or sell an underlying security.

In any case, this only happens because someone watches the bank's books. The people who do this are the 'balance sheet management' guys. Without them, the bank couldn't underwrite deals, couldn't put prices into the markets, and couldn't hold any securities overnight. They are going to have a system that tells them what BoA's balance is in (more or less) real time with each of the central banks for which they are a clearer.

They are going to know if the bank as a whole is long or short USD, GBP, EUR, CHF, etc., and they are going to have to manage the balances by either lending out surplus cash or by borrowing from the market (or from the central bank itself) to finance any shortfalls. For all currencies, BoA is going to have an agreement with the pertinent central bank on how short it can be overnight. In some emerging markets currencies, there may be limits on how long they can be as well.

In any case, they use standard loans and depos, currency swaps, OIS, short-dated fixed-for-floating swaps, and sometimes cross-currency swaps. They would have made a fortune last year (almost surely) by obtaining long-dated USD/GBP/EUR funding early in the crisis, and then lending it out on a daily/weekly basis at a much higher implied yield than they should have been given.

It's probably one of the least understood portions of the trading floor. But they are one of the most important desks (even if what they do is fairly vanilla).