This study seeks to identify the factors that accounted for Greek commercial bank profitability. Our aim is to isolate the characteristics and the management strategies that are common to high-performance financial institutions but are absent among the low-performance ones. The main data consist of the 1977-1986 income statements and balance sheets for a sample of eight Greek commercial banks. The emphasis of the analysis is more upon the empirical evidence and less upon the theoretical grounds. The first chapter describes and analyses the Greek financial system. The second chapter explores the profitability path of the sample banks during the period studied and subsequently ranks the firms according to their earnings for the whole period examined by employing a normalization criterion. The relationship between Greek bank earnings performance and their balance sheet structure is investigated in chapter three. This is done by describing and estimating a statistical cost accounting model. Chapter four examines the link between interbank profitability and various financial ratios (i.e. a financial ratio comparison approach). Chapter five analyses the market concentration in Greek commercial banking and its influence on earnings (i.e. the Structure-Conduct-Performance hypothesis). Finally, chapter six is concerned with scale economies in the preceding industry.