This paper examines the phenomenon of receptive multilingualism where speakers of two different languages communicate through each speaking his/her own language and understanding the other s. Comprehension in such an interaction is aided by the speaker and the listener employing linguistic, discourse-pragmatic and other features which represent strategies of accommodation (i.e. reduction of linguistics dissimilarities). This phenomenon is not presented as an alternative to interpreting, but in the context of interpreters who work from or into a language which is closely related, but not identical to the language spoken by one of the participating clients. Background information is provided from language pairs with a high level of mutual intelligibility and the experiences of interpreters, while the focus of the data sample is on 23 interpreters who have accreditation in one, two or three of the following closely-related languages: Bosnian, Croatian and Serbian. Responses are elicited on the following: self-reported incidence of accommodation in noninterpreted interactions; linguistic and ethical protocols when a different, but closely-related language is used by a client; comments from clients about interpreters proficiency and ethnicity; attitudes on the distinctiveness of the three languages and future intelligibility. Informants linguistic behaviour is analysed according to the number of accreditations held and, in general, those with three accreditations report the highest levels of accommodation.