During the last quarter of the 20th century, there have been considerable developments in the international financial system: deregulation, liberalization, internationalization of goods and capital flows, innovations of financial instruments and transactions, important developments in communication technology and increased competition. In this context, we try to elaborate the impacts of these developments on financial crises and the restructuring of financial regulation to prevent financial crises in the world, especially in Turkey. The November 2000 and February 2001 crises in Turkey have been analyzed in detail in the light of these developments.