Autonomy in Subnational Income TaxesThere are important differences between constituent units of federal or quasi federal states in OECD countries with respect to both powers for taxation of personal income and the use made of such powers, if any. Subnational Tax Autonomy in OECD Federations examines tax autonomy as a powerful tool in setting tax rates. Two key issues are examined in detail: first, why proposals giving more power to set tax rates have been implemented (Spain), put