Open Decision Making

One of the largest open data projects in the Netherlands. Standardized meeting data and API from more than 270 municipalities and provinces.

Addition to online democracy

In 2015, we started Argu to give people more influence in our democracy. With this e-democracy platform, we had developed a new way to have a say, making it easier than ever before to participate in decisions made in your municipality from behind your computer. But we noticed a problem: the online participation in Argu ran parralel to the formal decision-making within municipalities. As a result, there was not enough feedback to residents about what happened to their ideas.

We therefore wanted to use data from formal decision-making within municipalities to improve participation in Argu. We envisioned how we could link council meeting agendas with questions to residents, and how we could share decisions and votes during meetings with residents to keep them optimally informed.

From Open Council Information to Open Decision Making

We contacted the Open State Foundation (OSF), an organization dedicated to open data in the Netherlands. Together we lobbied the Lower House to make their data open, and we were the first in the Netherlands to be allowed to work with their data. Not entirely coincidentally, OSF was then also working with the VNG to make the data of city councils open, in the Open Council Information project. After OSF made the first links to meeting systems, we were commissioned by the VNG to improve the search engine and scale up the project. In one year we went from 7 to almost 100 councils connected. This made Open Council Information one of the largest open data projects in the Netherlands. Next, OSF was also working with a number of provinces. This project was called Open States Information. Because we wanted to show both data sources in one interface, in 2019 we chose to keep the whole thing under the name OpenDecisions. In subsequent years, we made sure that new municipalities were added, and maintained the interfaces with the meeting systems.

From OpenDecision Making to PLOOI

In 2022, the Open Government Act took effect, which requires municipalities to open up council information, among other things. The government organization KOOP was commissioned to create software for this, called PLOOI. It is planned that PLOOI will soon replace Open Decision Making.


OpenDecision Making consists of the following components:

  • Extract, Load & Transform (ETL) pipeline, written in Pyhton. This systeem fetches the data from various sources (Notubiz, Parleaus, iBabs and more) and converts it to a standaradised format.
  • Search back-end, based on Elasticsearch. This enables full-text search.
  • Front-end, gebaseerd op React. This is the responsive web interface that users see.

Read more about the technology in our blogpost.

The code is open source on Github.

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