Museums provide immaterial services of information goods; the agency relation may be assessed as for other public utility concerns, by appropriate indicators. In the first part, methodological problems are analysed focusing on the two main missions of the Museum, of conservation and supply of services to the public by considering efficiency, effectiveness and distribution issues, from stocks and flows points of view. The second part considers the various situation and performance indicators for recording and material preservation of the stock; and for services to the public (opening times, shares of items exposed and related facilities, etc.). Size and composition of visitors flows and of receipts flows are important indicators of outcome. JEL Classification: Z10