Fiscal decentralisation is notoriously difficult to measure. The common indicators such as the share of sub-central in general government spending or revenue often provide an imprecise or even misleading picture of intergovernmental fiscal frameworks. Since discretion over the budget is a central aspect of fiscal autonomy, the OECD has developed a more refined set of decentralisation indicators over the last decade. This chapter first presents the indicator on sub-central tax revenue autonomy, followed by the indicators which reflect the restrictions attached to intergovernmental grants. The third section establishes the criteria that should help find the dividing line between tax sharing and intergovernmental grants, two fiscal arrangements that are often difficult to disentangle. For illustrative purposes, results are presented for the year 2005. Finally, the results of a pilot study developing a set of spending power – or spending autonomy – indicators for a few OECD member countries are presented.