La definizione del prodotto delle banche

The aim of the paper is to account for the choice of a definition of the banking output suitable for the efficiency analysis of the italian banking system. A short survey of the literature allows to underline that the variety of definitions is linked to the empirical background and or to the analytical choices more than to different models of banking firm. A brief excursus of the evolution of the italian banking system in the last decades help to justify the choice.