In theatre, inequalities are often staged, in order to establish differences, mark out territories or produce identities. Such processes of demarcation, wherein 'foreign' codes such as dialects, pictures, different text genres, habitus, forms of movement and clothing are sometimes used, are to be found in various epochs and cultures. In the work of sociolinguist Ben Rampton, these are referred to as 'crossings'. The contributions in this volume ask questions from different perspectives: who communicatively and symbolically appropriates foreign codes? When, why and how does this happen? And in which contexts does it become an instance of crossing?