Federal states are economically stronger  Federal states are able to remove trade barriers between members which would otherwise exist if there were independent states (such as difficulties in moving goods due to borders). This increases internal trade and economic growth and encourages investors.1 Federal units are able to share resources and concentrate on producing what they are best at (called comparative advantage) at a better economy of scale. Even in cases of agreed free trade areas between states, there is no overarching authority to ensure timely compliance to agreements.2Finally, larger economic units are more able to influence international trade regimes.3 1 EU Business, 2007, 'EU Single Market- benefits,' Department for Business, Enterprise and Regulatory Reform, 2007, 'Guide to Benefits of the EU,' 2 BBC , 2011, 'US and Mexico end cross-border trucking dispute 3 Stanford Encyclopedia of Philosophy, 2010, 'Federalism