The presenters and their colleagues created an online corpus (released in 2023) containing six hours and thirty-nine minutes of audio recordings and transcripts of conversations between 18 Japanese (predominantly low-proficiency level) university learners of English and 18 foreign (mostly advanced level) participants of eight different nationalities, for all of whom English was not their L1. Following each conversation, semi-structured interviews were conducted (and audio recorded) with each participant separately to gain insights into their perceptions of their own communicative capabilities, those of their interlocutors. In this talk, the presenters discuss their findings based on thematic analysis of participants’ responses from the post-interviews. Analysis of the post-interview responses revealed that, by and large, the Japanese participants perceived their linguistic limitations as main hinderances in their ability to communicate effectively. The foreign participants, in contrast, reflected more on the effective use of language by highlighting various accommodations strategies they employed to help avert and overcome problems of nonunderstanding.