English is the number one language of business communication today. However, sometimes various languages are applied in one discourse, which may lead to opaque sequences. Thus comprehension of utterances in a language that was not learnt by one of the participants is necessary in order to achieve non-linguistic goals. Participants in international business encounters cannot rely on their linguistic knowledge alone, but have to make use of different forms of knowledge. This article discusses examples of situations in which comprehension has to be achieved although the participants’ linguistic knowledge alone is not sufficient for this task. A qualitative-interpretative approach is used to explain how participants achieve comprehension and the capacity to act in linguistically opaque situations. The examples discussed are taken from a corpus of authentic business negotiations.