Most people don't realise that the foreign exchange market was regulated very differently from other financial markets for a long time. Regulators acknowledged that the market was so liquid, transparent and competitive that front-running simply wasn't an issue and, in fact, was an appropriate way to fill client orders without exposing oneself to unnecessary risk.

Here's an article from May 2006 about the debate over whether the market needs best execution regulations imposed upon it: http://www.euromoney.com/Article/1039431/From-the-archive-Do...