This chapter summarizes the theoretical findings of the book concerning the architecture of grammar. The notion ‘construction’, a systematic correspondence between form and meaning, appeared to be very fruitful in describing the morphology of Dutch. Paradigmatic relations between words, and between words and phrases are essential for the analysis of Dutch morphology. The interaction between inflection and derivation in Dutch implies rejection of the split morphology hypothesis. A proper theory of morphology requires us to conceive of the grammar and the lexicon of Dutch as forming a multidimensional network of relations between (morphological and phrasal) constructional schemas of various degrees of abstractness, between these abstract schemas and the individual words and phrases by which they are instantiated, and between individual words and phrases. The detailed study of one subsystem of one language, the morphology of Dutch, gives us insight into the kind of conditions of adequacy that any theory of the architecture of grammars of natural languages must meet.