The symposium Language in Contact; Yesterday–Today–Tomorrow took place June 21–23, 2017 and was organized by The Graduate School Language & Literature Munich - Class of Language. Scholars using interdisciplinary approaches were invited to Munich and conveyed both traditional and innovative insights into the vast field of language contact. This included both diachronic (Yesterday) and synchronic contributions (Today) as well as papers discussing the future of contact linguistics (Tomorrow). At the symposium, language contact was defined in a broad sense as the language that emerges when speakers of different languages influence one another’s speech; this brought together multiple areas of linguistic study ranging from language change and language policy to language acquisition and language processing. Key to the conference was connecting what we can learn from past instances of language contact that will help us understand language phenomena in present and future research.