The Danube Commission is concerned with the maintenance and improvement of navigation conditions of the Danube River, from its source in Germany to its outlets in Romania and Ukraine, leading to the Black Sea. It was established in 1948 by seven countries bordering the river, replacing previous commissions that had also included representatives of non-riparian powers. Its predecessor commissions were among the first attempts at internationalizing the police powers of sovereign states for a common cause.

The Central Commission for the Navigation of the Rhine is an international organisation with five member countries, whose function is to encourage European prosperity by guaranteeing a high level of security for navigation of the Rhine and environs. Founded in 1815, it is the world's oldest international organization still in operation. It has been based in Strasbourg, France, since 1920. Lucia Luijten from the Netherlands has been its Secretary General since November 1, 2021.