In short, there isnt any. Not like the Forex trading is completely unregulated, but there isnt such thing a SEC (Securities and Exchange Commission) for the Forex market. There is no central location and the company that would own the market (like NYSE Euronext owns New York Stock Exchange). Decentralization of the modern foreign exchange market is its greatest advantage and one of its biggest problems. And while the market itself remains unregulated the market participants are, in fact, regulated by various authorities, depending on the country where the given participant resides or does his business.
NFA (National Futures Association) and CFTC (Commodity Futures Trading Commission) are obligatory regulating organizations for the Forex brokers that are based in United States or want to legally deal with the U.S. residents. While spot Forex trading has nothing to do with the futures or commodities, these organizations set the rules for how the retail Forex market should work in United States. Some of the rules protect the traders (e.g. by setting high own capital requirements for the brokers) and some just make traders life harder (e.g. the tons of documentations required to register with a broker and the latest no-hedging rule). Anyway, traders (even those from U.S.) still have the option not to trade with the NFA-registered brokers, so, theres nothing bad in having such institutions as NFA or CFTC.
FSA (Financial Service Authority) regulates the Forex brokers that are based in U.K. or are dealing with the British traders. The U. K. regulation is much lighter than the one in U.S., so traders usually find no difference when they are dealing with the FSA-registered broker. If you want a regulated U.K. broker, just look if its registered with FSA. But dont expect it to be much more reliable than the unregulated brokers.
SFBC (Swiss Federal Banking Commission) requires all Forex brokers that are based in Switzerland to obtain the real Swiss banking license and thus become a regulated banking institution. Thats a good thing for those traders that are registered with the Forex brokers that got such license, because Swiss banking regulation is one of the best in the world and those institutions that fulfill all the requirements can be certainly considered reliable. On the other hand, obtaining such a license is a long and expensive way; this fact is making some of the Forex brokers to move out of Switzerland.
Some Forex brokers are regulated by the European and other banking laws as they are registered as the banking institutions in the respective countries. Such brokers can be considered the most reliable ones, but for the common retail trader dealing with them isnt easy as they usually require high minimum account deposit and a lot of paperwork.
The majority of other regulatory bodies provides almost no strict requirements for the Forex brokers and is plainly nominal. If you see a broker registered on Seychelles or British Virgin Islands, or some other «offshore zone» it doesnt mean that its thoroughly checked and audited. Of course, it doesnt also mean that its a scam broker. Some Forex brokers prefer to stay offshore for a lot of advantages and some traders prefer those brokers for their own reasons. When you choose your broker, be sure to select the one with the appropriate type of regulation that fully fits your trading needs.
If you have your own opinion or questions on Forex market regulation, feel free to leave it in a comment to this post.