This book provides a usage-based perspective to the study of multi-word compounding, analyzing the structural, functional and cognitive aspects of tripartite compounds (e.g. day care center, football game, hotel bedroom). It highlights the heterogeneity of these word-formation products, but also carves out surprising differences to two-word compounds. In order to reveal the step from two-word compounding to multi-word compounding, the book explains why only some compounds are used productively for the formation of more complex compounds. Building on the idea of entrenchment, it provides a theoretical account that allows understanding speakers' ability to produce multi-word compounds.