Research within the field of gender-fair language in multilingual contexts has until now mainly focused on translating gender in literary works and gender-inclusive language in machine translation. However, research on interpreting gender-fair language, focussing on gender beyond the binary, is still scarce. This is remarkable, considering the rising visibility and recognition of the LGBTQIA+ community and the fact that gender-diverse foreign-language persons rely on linguistic support, such as an interpreter, to express themselves across the language barrier in accordance with their gender identity. Moreover, there are challenges for the interpreter in using the right linguistic tools in the source and target language in order to shape the (linguistic) identity of the person in question. My research aims to explore gender-fair language use in interpreted interaction, with a focus on gender-diverse identities in service provision contexts. Through linguistic ethnography, interviews and a survey, I aim to explore interpreters' awareness and concrete handling of the linguistic and deontological challenges in the source and target language, as well as how their (linguistic) choices impact the conversation. Moreover, an experimental approach will give me insight into the effect of training on gender-fair interpreting.