The movement of globalisation, which is proceeding at increasing speed all around the world, is causing serious problems, especially for developing countries whose sectors have a low competition level. Because it is known that regional co-operation and integrations will help to prevent the ill economical, social, political and technological effects of globalisation which affect developing countries, movements of regional co-operation are expanding together with that of globalisation itself One of the most important such integration movements is the European Union. The Customs Union Pact, which was affected by the great integration movement of European Union and Turkey and has been in operation since 1996, still has the distinction of being the most important economic integration pact in Turkey history. This pact has both positive and negative effects on many sectors of the Turkish economy, such as the textile and clothing sectors, which are among the most important areas of the country industry. Aspects of these effects can provide us with important information about the future of these sectors.