This article introduces the Parallel European Corpus of Informal Interaction (PECII), a multi-language video-corpus of social interactions in a range of informal settings and activity-contexts. After describing the basic motivation for its compilation, the design principles that underlie its composition and the data it contains, we illustrate PECII’s usefulness for comparative Interactional Linguistic (IL) and Conversation Analytic (CA) research. We do this by offering an analytic sketch of the practices people use to initiate turns that interfere with and seek to rectify another’s (problematic) behavior, focusing on their variability across languages and settings/activity-contexts. By maximizing the comparability of interactional data, PECII not only promotes the enhancement of cross-linguistic research in IL, it also opens up new avenues for exploring “cross-situational” variability (so-called “situation design”).