The research theme Number and measure investigates expressions of quantity, number, extent and degree from the perspective of their morphosyntax, semantics, pragmatics and acquisition. The linguistics of number and measure is an ongoing topic of considerable interest in the field, and one in which ZAS has a long history of significant and internationally visible contributions. Yet, despite decades of research, fundamental questions are still open: What are the syntactic and semantic building blocks in the expression of number and measure? To what extent is the grammar of number and measure universal vs. language specific? In what ways is it constrained by extra-linguistic cognition? How are such expressions deployed in communication? How are they acquired? We pursue theoretical research in these areas, addressing long-standing questions and opening new areas of investigation, while also seeking to make our findings available to inform applied research.