> what is the net benefit of currency arbitrage It means you can actually ask the question "how many dollars is a pound worth" and get a meaningful answer. If

> what is the net benefit of currency arbitrage It means you can actually ask the question "how many dollars is a pound worth" and get a meaningful answer. If arbitrage wasn't possible for some reason, and it's a natural phenomenon so that would have to involve pretty horrific levels of state-backed control, then the answer would be: "It's $X in London and heading down, was $Y in New York yesterday and heading up, and $Z in Chicago but you probably can't get an account there because it takes ages and requires special paperwork, and <thousands of additional prices>" You would then spend the rest of the afternoon attempting to figure out how the hell to do a basic international trade or FX transaction and by the time you'd finished reviewing the prices they'd have all changed again. Arbitrageurs seek out and correct fixable price disparities, thus enabling you to talk about one global price for a particular type of trade. This has tremendous value for everyone.