The European Statistical System is comprised of: Eurostat (the statistics office of the EU), the statistics offices of all the Member States (the different National Statistics Institutes) and other institutions that compile European statistics.

The European Statistical System guarantees that those European Statistics compiled in all the Member States of the European Union are reliable, following common criteria and definitions, and processing the data in an appropriate way so that it is always comparable among the different countries of the EU.

Currently, the ESS is fundamentally regulated by the European Statistical Law, passed in 2009 through Regulation (EC) 223/2009 of the European Parliament and of the Council.

European Union statistics are prepared, compiled and disseminated by both the European Statistical System (ESS) and the European System of Central Banks (ESCB).

The nucleus of the ESS is the European Statistical System Committee. Participating therein are Eurostat and the presidents of the national statistics offices of the member States and the countries of the EFTA. This Committee offers professional orientation for the planning, compilation and dissemination of European statistics, and is involved in the process of compiling and adopting the European statistical legislation development norms.

The ESS has an European Statistical System which includes the statistical planning for a period of five years. This Programme is passed by the European Parliament and by the Council. In order to ensure that users' needs are taken Into account when compiling the European Statistical Programme, the European Statistical Advisory Committee was created. It represents users, informants, academic and social institutions and the community administration.

Although the activity planning is carried out jointly among the National Statistics Institutes and Eurostat, the production of harmonised national statistics corresponds to the authorities of the Member States, whereas Eurostat collects the data provided by the States, analyses it, and based on this, offers comparable and harmonised figures, making it possible to define, undertake and analyse community policies.

Furthermore, Eurostat undertakes to ensure the coordination necessary to guarantee the functioning of this complex system (different languages, very diverse forms of administrative organisation, specific nomenclatures, etc.) and to ensure the coherence and quality of the data.