This book is the first on Cantonese that deals with the grammaticalization phenomenon systematically. Focusing on a group of twelve directional particles, this book tracks their grammaticalization pathways from full-fledged directional verbs, to directional particles indicating meanings relating to tense-aspect, modality, and quantification, in the post-verbal position. Some of these particles have undergone further grammaticalization to convey speaker's subjective as well as intersubjective stances. This book is also unique in its diachronic component. Examples in the book are drawn from various sources including early Cantonese pedagogical texts, Cantonese films, and contemporary Cantonese corpora, with data ranging from the mid-nineteenth century to the present. This book will be a valuable resource not only for all linguists interested in the development of grammatical forms, but also for teachers and students in conversation/discourse analysis, psychology, and anthropology interested in deepening their understanding of the interaction between language structure and use.