The article discusses different economic theories during the global economic crisis. It shows that the crisis exposed flaws in the idea of letting the private sector regulate itself. Instead, governments had to step in with new policies. Keynesian ideas, like government intervention during crises, were widely used. Central banks lowered interest rates and increased money supply, while governments implemented stimulus programs. The crisis led to a reevaluation of economic theories, highlighting the importance of considering market imperfections and limited government policies when creating new economic strategies.