Concordance analysis is widely recognised as one of the main techniques in a corpus linguist’s toolkit. However, despite a growing body of work critically exploring previously unquestioned mainstays of corpus methods (Mautner, 2015; Taylor & Marchi, 2018), this has not focused on concordance analysis specifically. In this paper, we aim to discuss issues that researchers may encounter when interpreting concordances. We begin in Step One with a cursory examination of 800 concordance lines in order to identify potential issues. In Step Two, we assess the distribution of those issues in a reduced sample of 200. As a result, we identify eight interpretability issues: noise in the corpus, non-standard syntax, unclear referring expressions, unclear quotation source attribution, technical terms/jargon, acronyms/initialisms, unspecific co-text, and lines unrelated to the research question. After reflecting on practical challenges, we discuss the epistemological implications of removing concordance lines uncritically and suggest ten recommendations for future work.