Southwest Finland has active cooperation with many regions on the shores of the Baltic Sea. The cooperation with the German region Meclenburg-Vorpommern has been very active since year 2000 (see joint actions and contacts here), as have been the implementation of joint agreements with the Northwest Russia and the Polish Pomerania. Without formal contracts the cooperation is even broader, traditionally with Sweden and Estonia.

The emphasis in regional cooperation is on the Baltic sphere and the Council participates in the realization of the Baltic Sea strategy.