− − − − − − that permits more than one official language to be used based on territorial or personal principles may also help to ensure the recognition of linguistic communities and contribute to the unity of linguistically diverse States. In such cases, the equal status or different scope of the use of official languages in various spheres must be clearly determined; States should not restrict the use of minority languages in the private sphere and any State-language requirements in the public sphere should be based on legitimate aims and be necessary and proportional; States should ensure that everyone, including persons belonging to minorities, is provided with adequate opportunities to learn the State language so that they can participate effectively and equally in the economic, social, cultural and political life of the State; Where a linguistically diverse State perceives and maintains a single official language as a tool of integration, allowing the use of other languages to some degree in public administration and services, education and the media can help accommodate the needs and promote the inclusion of minorities. The levels and nature of any language services and the incorporation of non-official languages into the public administration should be determined according to the specific circumstances of the communities concerned. Essential public services, such as healthcare, should have the capacity, to the extent possible, to also provide those services in minority languages when needed; Proficiency in the State language by all residents in that State is necessary for full and effective participation. In addition, language can be a powerful tool to enhance a shared sense of belonging. Therefore, it is legitimate to promote a State language through positive means and incentives, including accessible public programmes for learning that language; Language can also be used to exclude those deemed insufficiently proficient from specific roles or professions or from symbolic acceptance into a community. States should refrain from adopting policies to promote a State language that are disproportionate or are inadequately balanced with the linguistic rights of persons belonging to minorities; States should ensure that minorities enjoy sufficient support in maintaining and developing their linguistic identities. This can include guaranteeing the right to use minority or regional languages in private and family life and by supporting their use in private and in public. For example, States can provide signs, inscriptions, place names, street names and other topographical indications in the minority language or bilingually in the State and minority languages. Guidelines on Integration of Diverse Societies 53