The Markets in Financial Instruments Directive comes into force in the European Union on November 1, and firms will need to take more control over their trading processes as they are compelled to achieve and prove best execution for their clients.

The notorious best execution guidelines are spelled out in Article 21, which states that firms executing trades "must take all reasonable steps to obtain the best possible result, taking into account price, costs, speed, likelihood of execution and settlement, size, nature or any other consideration relevant to the execution of the order."