MiFID II is an EU directive that significantly expands the scope and requirements of the original Markets in Financial Instruments Directive (MiFID) implemented in 2007. MiFID II aims to strengthen financial stability, reduce systemic risk, and increase investor protection following the 2008 financial crisis. It broadens coverage to include more financial services firms and asset classes. Key changes under MiFID II include increased pre- and post-trade transparency, additional rules around algorithmic and high-frequency trading, and strengthened supervision of commodity derivatives markets. Compliance will require major operational changes for many financial services firms across areas like reporting, trading systems, research payments, and position limits.