The provisions of the Treaty on the European Union (EU) and, in particular, the Agreement on Social Policy (ASP) attached to the Treaty, envisage subsidiarity in social policy as a complex and innovative legal principie, which lies at the very roots of a di-versification of EC and national legislative and contractual sour-ces, at various levels, designed to regulate working conditions in the EU.
The ASP contemplates a «dual subsdiarity» in social policy:
A) a vertical subsidiarity concerning the sharing of regulatory powers between the Community and Memeber States;
B) a further horizontal subsidiarity, wich gives rise to a proce-dure of cooperation by the social partners towards establishing re-gulatory acts (at Community level) and a procedur of incorpora-tion of directives (at national level) or substitution of the regula-tory activity of European Community insitutions with collective autonomy. This is a new procedure for forming European Com-munity law based on collaboration between Community institu-tions and the social partners. The ASP defines the legal nature of such collaboration and its effects at both Community and national level