Nature national instruments
What is the character of the legal instruments adopted at national level to implement Euro-crisis law (constitutional amendment, organic laws, ordinary legislation, etc)?
Ordinary law governs changes to the budgetary process.
The transposition of Directive 85/2011 is done through ordinary law (see under VII.2 below).
The execution of the fiscal compact is laid down in a cooperation agreement, which ranks above ordinary law and decree, but lacks jurisdictional protection (see also under IX.4 below). 
Following articles 39, 127, 128 and 130 of the Constitution, the Special Act on Institutional Reform contains a provision on optional and obligatory cooperation agreements (art. 92bis). Some cooperation, for instance those with financial obligations, require parliamentary approval for each participating level of government. The cooperation agreement implementing the TSCG has obtained parliamentary approval, and takes rank above law and decree, but below special acts, the constitution, and international law with direct effect.
Have there been any constitutional amendments in response to the Euro-crisis or related to Euro-crisis law? Or have any amendments been proposed?
The Euro-crisis coincided with a major reform of the institutional structure of Belgian federalism. Amongst the numerous proposals for constitutional amendments, not one relates to the euro-crisis directly. The amendment to ensure an easier process of ratification of international treaties is a returning issue, but is not inspired by the euro crisis.
The phased process of constitutional change requires a declaration for revision indicating which articles are up for revision and a subsequent election, after which a two-thirds majority may revise those articles. This explains how, though some parties have come out in favour of a constitutional balanced budget requirement (e.g. Open Vld), no real amendment has been proposed.
If national constitutional law already contained relevant elements, such as a balanced budget rule or independent budgetary councils, before the crisis that are now part of Euro-crisis law, what is the background of these rules?
The jurisdiction of the Court of Auditors, reviewing the execution of the budget as approved by Parliament is laid down in article 180.
No other relevant provisions.
Purpose constitutional amendment
What is the purpose of the constitutional amendment and what is its position in the constitution?
Relationship with EU law
Is the constitutional amendment seen as changing the relationship between national and European constitutional law?
Have there been changes to organic laws or other types of legislation that are of a different nature or level than ordinary legislation, in relation to Euro-crisis law or the budgetary process?
See with respect to the cooperation agreement used for implementation of the Fiscal Compact’s Balanced Budget Rule, section IX.4 on the Fiscal Compact.
Constitutional amendment and ordinary law
If ordinary legislation was adopted in conjunction with a constitutional amendment, what is the relationship between the two?
Perception source of legal change
In the public and political discussions on the adoption of ordinary legislation, what was the perception on the appropriate legal framework? Was the ordinary legislation seen as implementing national constitutional law, or Euro-crisis law?
What other information is relevant with regard to Belgium and to changes to national (constitutional) law?
No other relevant information.