This paper examines the importance of fiscal autonomy in the analysis of decentralization. Using new data published by the OECD (2001 and 2002), it reproduces several indicators and proposes new measures of decentralization that take into consideration su-bnational governments' autonomy over their revenues. Two models are reproduced: Davoodi and Zou (1998) on decentralization and economic growth, and Oates (1985), on decentralization and public sector size. Some evidence suggests that fiscal autonomy positively affects economic growth. Also, it seems to affect the size of the state, but evidence on this relation is limited. Despite some statistical weaknesses, there are sufficient indications to argue that sub-national governments' fiscal autonomy should be a major concern when measuring decentralization.