When countries reach agreements with each other, they usually write these down in treaties. As long ago as 1963 a few countries drew up an agreement on cooperation along the Rhine. The Convention on the Protection of the Rhine in its current form was signed in 1999 by France, Germany, the Netherlands, Switzerland, Luxembourg and the European Commission. They also set up a commission to comply with the agreements and to make and implement plans. A commission is a group of people with a special task. In this case, the task is to protect the Rhine. This is why the commission is called the International Commission for the Protection of the Rhine (ICPR). Its office is in Koblenz, Germany.
The commission often cooperates closely with Austria, Liechtenstein, Belgium (Wallonia) and Italy, because these countries are in the catchment area but not represented on the commission.