The principle of subsidiarity, as defined in Article 3b of the Treaty on European Union, concerns the relationship between the Community and the member states. Article 3b specifically provides that
In areas which do not fall within its exclusive competence, the Community shall take action, in accordance with the principle of subsidiarity, only if and in so far as the objectives of the proposed action cannot be sufficiently achieved by the Member States and can therefore, by reason of the scale or effects of the proposed action, be better achieved by the Community.
In accordance with this provision, matters of domestic policy will remain within the competence of the member states except where Community action can achieve the objectives better.
The objective of economic and social cohesion set out in the Treaty relates to reducing the disparities between the levels of development of the various regions and the backwardness of the least favoured regions. Ireland is one region from an EC viewpoint and the objective will be to bring the country as a whole closer to the overall level of development in the Community.