In general terms, regional trade blocks are associations of nations at a governmental level to promote trade within the block and defend its members against global competition. Defense against global competition is obtained through reducing tariffs on goods produced by member states, import quotas, government subsidies, onerous bureaucratic import processes, and technical and other non-tariff barriers. Since trade is not an isolated activity, member states within regional blocks also cooperate in economic, political, security, climatic, and other issues affecting the region. In terms of their size and trade value, there are four major trade blocks and a larger number of blocks of regional importance.