In this lecture, professor Francesco Bilancia discusses the constitutional contemporary architecture of the Italian State-regions relations as implemented by the 1999 constitutional reform. An important constitutional amendment in 2001 deeply changed the regional legislative power, so that the analysis of constitutional constraints and limits on the regional powers brings the attention on the fundamental role of the Italian Constitutional Court on these issues. After the introduction of the balanced budget rule by a constitutional amendment in 2012, and because of the European Monetary Union related conditionalities and obligations, Italian regionalism is now facing an authority migration, brought by a concrete recentralizing counter-wave in the Constitutional Court case law and State legislation.