In 1995, Germans and Poles, i.e. the former and the present inhabitants of the Sulęcin Region, signed an agreement concerning cooperation and implementation of joint enterprises for the reconciliation of both nations. A symbol of the agreement was the Tree of Reconciliation and Good Neighbourhood, planted in May 1995 in the Market Square in Sulęcin.
Another step in the development of the Polish-German cooperation was the idea of constructing the Fountain of Good Neighbourhood in the Market Square. The implementation of this project was possible due to financing from the PHARE CBC fund and support of the German town Beeskow. The Fountain of Good Neighbourhood is not only a symbol of fruitful cooperation between the two towns, but also a symbol of the Poles' and Germans' common history, and the market square in Sulęcin has become the place of international meetings and promotion of the idea of European unity and international agreement.
In 1997 representatives of Sulęcin and Beeskow signed an agreement concerning bilateral cooperation in the fields of culture, sports, tourism and history. This agreement was signed with a conviction that the cooperation between Sulęcin and Beeskow will be the beginning of united Europe's development. Due to the relations with Beeskow, cooperation was also established with another German town, Kamen. This cooperation was documented with the signing of partner agreements between Sulęcin and Beeskow and Sulęcin and Kamen on 3 May 2002 in the Market Square in Sulęcin.
The signing of both partner agreements resulted in the establishment of cooperation between Polish and German schools, kindergartens, nursing homes, senior citizens, artists, firemen, anglers, cyclists, sportsmen, and apiarists.
Poles and Germans also participate in the preparation and implementation of joint projects executed with the European Union's financial support.
On 31 May 2003 in Kamen the founding act of "the Circle of Befriended Towns" was signed by the following towns: Beeskow (Germany), Kamen (Germany), Unkel (Germany), Eilat (Israel), Bandirma (Turkey), Ängelholm (Sweden) and Montreuil – Juigne (France). According to this Act, the inhabitants of the towns whose representatives have signed it are obliged to cooperate more closely and to build a common Europe, free of prejudice.
In the late 1990s relations between Sulęcin and the German town Friedland were established. As a result of this cooperation, on 1 May 2005 a partner agreement was signed between the two towns. Pursuant to the agreement, cooperation between Polish and German schools, kindergartens, cyclists, senior citizens, artists, anglers and firemen from Friedland and Sulęcin was established.
Apart from the three partner towns in Germany, Sulęcin has also a partner town in Poland. It is Nowy Tomyśl located in Greater Poland. The partner agreement between Sulęcin and Nowy Tomyśl was signed on 1 May 2005 in Sulęcin. Also this cooperation has had measureable effects, that is, the establishment of cooperation between schools, anglers, artists, and cyclists from the two towns. The councillors from both town councils support one another in their work as well.