This book argues for a conception of linguistic organisation involving the factorisation of syntactically relevant information into at least four parallel dimensions of structure: semantic structure, argument structure, grammatical function structure, and grammatical category structure. The author argues that these dimensions are co-present, being simultaneously accessible for the statement of regularities. Different principles of grammar may either reinforce one another, or conflict with one another. The observed facts of a language then turn out to be the result of interaction among the reinforcing and conflicting principles. Tara Mohanan was born in Kerala, India, spent her childhood in various parts of Northern India, and grew up speaking both Malayalam and Hindi as a mother tongue. Tara now lives in Singapore with her husband and daughter, and teaches linguistics at the National University of Singapore.