The purpose of town twinning is the voluntary coming together of people across borders. They are intended to promote peaceful coexistence across borders and serve economic and cultural exchange.

In the past, cities have therefore looked for suitable twin towns. The size of the city, the structure of the city (e.g. rural or industrial) and, for example, the club life play a special role. Beforehand, it is usually checked whether there are already any private contacts between citizens, local politicians or schools and a municipality abroad that could be intensified and could then lead to a town twinning. If such contacts do not exist, municipalities "willing to partner" are also referred by supra-local organizations.

Many cities that wish to enter into an international partnership are also published on the website of the "Council of European Municipalities and Regions". Model contracts for partnerships are also published here. If various criteria are met, a visit by the head of administration (mayor, local council) and a corresponding return visit take place. A positive response usually leads to the formal establishment of a town twinning, which is sealed with the signing of the twinning certificate.

In the period that follows, annual visits are often organized depending on the commitment of the towns. The initiative for this comes either from the city administration or occasionally from associations. The visitors are then usually accommodated with private hosts, which promotes the growing together of the nations. If clubs take part in such an exchange, it is not uncommon for joint events to be organized, such as games (in the case of sports clubs) or concerts (in the case of music clubs or choirs).

Municipalities that maintain intensive European partnership contacts can also apply for awards from the Council of Europe. There are the following forms of awards: "European Diploma", "European Plaque", "Flag of Honor" and "European Prize". These are awarded in stages, i.e. an application for the European Diploma must be submitted first. If this is awarded, the municipality can later apply for the European Plaque etc.

A weaker form of town twinning is town twinning. It is usually limited in time or only relates to certain projects within a relationship. An even weaker form is town-to-town contact, which is only a loose relationship between two cities or municipalities (examples here include the numerous contacts between German-German municipalities after reunification).