In exercising their rights to effective participation and self-determination, minorities and indigenous peoples face several challenges in Germany and Poland. Both states are democra-cies, which are characterized by the rule of majority. Due to the numerical inferiority of minority groups, special measures are necessary in order to guarantee that their participation in political decision-making processes is not mere formalism, but effective. This obligation of the German and Polish societies to explicitly protect their weakest members indicates that with regard to mi-norities there is a necessary connection between law and morality. However, there is still no consensus among states on a legally binding definition on what is to be considered a ‘minority’ or an ‘indigenous people’. Taking into account the ‘com-plex and delicate question’ of these ‘informal’ minorities, a holistic approach to the concept of minorities is developed that enables it to serve as a ‘catch-all’ phrase that allows to include in-digenous peoples and other ‘traditionally’ existing groups in a certain area as well as ‘newly’ immigrated groups into the concept of minorities. The issue of ‘diversity management’ regained political importance when the number of asylum seekers and economic immigrants began to rise throughout Europe. However, the recent immigration movements did not affect the rights of ‘traditional’ minorities legally. Rather, they affected the possible enjoyment of future rights by provoking a right-wing shift in policy that is based on a xenophobic attitude. In order to achieve a more effective implementation of the existing rights of minorities to effective participation and self-determination in the future, the proposed approach to the concept of minorities serves as a point of departure. It could be implemented into the German-Polish Treaty of Good Neighbourship and Friendly Cooperation and thus set a new common standard of what is to be considered a minority, paying special attention to cross-border minorities like the Silesians and their participatory rights on a regional or municipal level. The GPTGNFC could also be amended with new rights to internal self-determination of minorities that base on the already existing regulations within both states in order to further realize the right of minori-ties to self-determination and effective participation in political decision-making. In addition, the multicultural education would help prevent populism and xenophobic prejudice and thus con-tribute to an integrative society that offers a place for everyone, irrespective of one’s cultural, ethnic or linguistic background. Also, recognizing and strengthening communal groups within the existing state system though collective rights would help resolve fundamental structural problems of Germany and Poland.