Famously, multilinguals are not multiple monolinguals in one person – nor do they have individual grammars for different languages. Diasystematic Construction Grammar, a usage-based constructionist approach to language contact phenomena, is built around the central insight that there are no language boundaries within the constructicon. It is a simple idea, but it has far-reaching consequences. Most importantly, there is a division of labour between language-specific and language-unspecific constructions that together form a multilingual speaker’s constructicon. Language-unspecific constructions are not restricted to syntax or morphology: With typologically similar and/or genetically related languages, even words and parts of words can be language-unspecific, and – for multilinguals – even monomorphemic words are often compositional in a quasi-inflectional way. This talk focuses on the constructional organization of multilingual knowledge at the word level and below.