The project relies on fairly unique data that previous literature has investigated only scarcely. Data collection covers social interactions that happen a) between unacquainted persons, b) in unplanned ways, c) in institutional and public spaces, d) in multilingual settings. Two types of gatherings have been identified. The first can be described as a symmetric ordinary encounter, in which participants happen to meet coincidentally: this is for example the case of people sharing the same space in a park, hence beginning to chat, or of pet owners casually meeting when walking their dogs. The second type of gathering can be characterised as an asymmetrical institutional encounter, in which one person initiates the contact with another, typically in an institutional place where a service is offered, or in public space where someone addresses a passer-by as they request a signature, money, or hand out a flyer, try to sell a product, etc. Recordings are made inside public and institutional buildings, as well in as outdoor public places.