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TOOP Project - The Once-Only Principle Project

  • Research and Innovation
  • European
  • Cloud
Last updated: 2021-09-15 06:57

Strategic Goals

he once-only principle (OOP) needs to be seen in the context of public sector digitalisation. It means that citizens and businesses provide diverse data only once in contact with public administrations, while public administration bodies take actions to internally share and reuse these data – even across borders – always in respect of data protection regulations and other constraints.

The concept of the OOP focuses on reducing administrative burden for individuals and businesses by re-organising public sector internal processes, instead of making citizens and business users adjust to existing procedures.

So far, many European Union countries have started to implement the once-only principle at a national level, while its cross-border implementation is still fragmented and limited to a very few services. In view of its contribution to the realisation of the Digital Single Market in Europe, the European Commission is strongly promoting the implementation of the OOP across borders. Therefore, once-only is one of the underlying principles stated in the European Union’s “eGovernment Action Plan 2016-2020” and is part of several initiatives related to the European Digital Single Market.

Solutions Developed / Used

The main objective of TOOP is to explore and demonstrate the once-only principle across borders, focusing on data from businesses. Doing this, TOOP wants to enable better exchange of business related data or documents with and between public administrations and reduce administrative burden for both businesses and public administrations.


Start Date 01/01/2017
End Date 30/06/2019
Project Focus
  • Broker
Geographical Scope
  • European
  • Cloud
Cloud Delivery Model
  • PaaS
Project Life-Cycle Stage
  • Research and Innovation
  • Public Administration
Specific Domains Targeted
  • Green Deal


    Academic/Research Organisations
  • Estonia
     Tallinn University of Technology (Estonia)

Overall Budget
  • €8,000,000.00
Official Website