The subsidiarity principle is intended to ensure that decisions are taken as closely as possible to the citizen and that constant checks are made as to whether centralized action is justified in the light of the possibilities available at national, regional or local level.
Centralized structures can be effective in policy formulation and in national and regional planning, but they are rarely effective in local project implementation. Both an absence of understanding of local circumstances by the external body and a sense, within the recipient community, that a solution is being imposed from outside, with a commensurate loss of community interest, can conspire to undermine local projects.
This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities. Particularly within the framework of planning and implementing water projects, Agenda 21 recommends applying the principle that decisions are to be taken at the lowest appropriate level, with public consultation and involvement of users.
Article 5(f) of the [1999 Draft Protocol on Water and Health to the 1992 Convention on the Protection and Use of Transboundary Watercourses and International Lakes], states: Action to manage water resources should be taken at the lowest appropriate administrative level.
Within Europe, the European Council (December 1992, Edinburgh) defined the basic principles underlying subsidiarity and laid down guidelines for interpreting Article 5 (former Article 3b), which enshrines subsidiarity in the [EU Treaty]. Its conclusions were set out in a declaration that still serves as the cornerstone of the subsidiarity principle. The Treaty of Amsterdam has taken up the overall approach that follows from this declaration in a Protocol on the application of the principles of subsidiarity and proportionality annexed to the EC Treaty.
Many states have drawn up [National Environmental Health Action Plans] (NEHAPs) and are now preparing to implement them. A NEHAP defines the national framework but, in accordance with the principle of subsidiarity, its successful implementation requires the majority of actions to be undertaken at the local level. This may be achieved in a variety of ways. The formal development of local environmental health action plans (LEHAPs) is one way of doing this. Another is to use existing systems and plans such as local development plans. Within existing systems, implementation of the NEHAP by local authorities may give additional impetus to their work on local Agenda 21 issues and the Healthy Cities network (although some of the problems addressed in NEHAPs are rural rather than urban). The integration of plans and initiatives at the local level will bring similar benefits to those from integration of plans at the national level, and many components of a NEHAP may be carried through under the auspices of another plan: these are other examples of a win-win situation.
Decisions and actions to manage activities relevant for transport should be taken at the adequate administrative level and as closely as possible to the citizens.
The principle of "subsidiarity" permits the European Union to incorporate specific actions at local, regional, national and European level allowing European Union structures to support and intervene where those levels need to be complemented, especially to respect Community or international commitments. Moreover this principle is accepted voluntarily by the EU Member States and avoids conflicts of competencies, supporting the principle of solidarity in a pragmatic way.