The Linguistic Theory and Language Acquisition group investigates language acquisition against the background of the formal and functional structure of natural languages. We study different settings, as well as comparisons of these settings, including first language acquisition in monolingual children, language development of children who grow up in bilingual or multilingual homes, (early) second language acquisition in children, and language development in children with developmental disorders. All these settings are relevant for taking a broader perspective on the process of language acquisition, aiming at studying the relevance of various factors: input factors such as multilingual exposure, maturational factors such as age and cognitive development, and processing factors such as transfer and disorders. In order to disentangle the roles of innate learning mechanisms (‘biases’) and language-specific input factors in acquisition processes, a cross-linguistic and/or cross-population perspective is crucial.  We actively transfer our knowledge of language acquisition to communities and stakeholders outside university by means of various activities, including developing diagnostic tools for professionals; providing support to municipalities, schools and teachers; organizing and participating in workshops on raising bilingual children; setting up websites for multilingual families; publishing about multilingualism aimed at schools and educators; participating in interdisciplinary European projects.