This paper introduces a political-economy framework to investigate the role of finance in economic instability and crisis. It is argued that the rise in income of rentiers, private bankers and other groups of financial capitalists merits responsibility for the economic and financial instability, unemployment and an increasing risk of deflation and crisis that many capitalist countries face today. The paper considers a Marx, Keynes and Minsky problem associated with a rise in financial profits and argues that the impact of finance on economic activity is, to a large extent, determined by institutional and structural factors