This document discusses economic integration at three levels - global, regional, and bilateral. It outlines four stages of economic integration: free trade areas, customs unions, common markets, and economic unions. Free trade areas eliminate internal tariffs but maintain external tariffs, while customs unions have common external tariffs. Common markets integrate free movement of goods, services, capital and labor. Economic unions coordinate fiscal and monetary policy in addition to a common market. The document also covers some economic effects like trade creation and diversion, as well as issues like trade deflection and national sovereignty.