The aim of this paper is to investigate alignment in L1–L2 dialogue. More specifically, it examines to what extent alignment in L1–L2 is different from alignment in L1–L1 dialogue. It investigates different variables that may affect linguistic alignment in the course of L1–L2 dialogue. As more variables, such as differences in language proficiency of interlocutors, affect the linguistic alignment in L1–L2 dialogue, it appears that linguistic alignment in L1–L2 dialogue is different from linguistic alignment in L1–L1 dialogue both quantitatively and quantitatively. The paper also discusses the mechanisms that permit lexical alignment during dialogue. This study interprets the alignment process in terms of the activation threshold hypothesis (Paradis 1993) and a link is made between the activation threshold hypothesis and Pickering and Garrods’ (2013) account that language production and language comprehension are interwoven. Based on Swiss multilingualism, language selection is proposed as the macro-linguistic alignment process.