This book explores the diachronic emergence of the verb have in English in its various grammatical uses. The development of grammatical functions of have is analysed from pragmatic-semantic, morphosyntactic and phonetic angles. Apart from the well-known and formerly studied cases of the rise of perfect and obligative have, the author describes the developments of the had better structure as well as causative have which have not received much scholarly attention thus far. He shows that the first examples of the fully grammaticalised constructions with have generally appear earlier than it is commonly believed. He also offers possible motivations behind the growth of obligative and causative have. This book proves that the changes leading to the rise of new grammatical constructions occur in a specific order: pragmatic-semantic changes precede morphosyntactic changes and phonetic reductions are the last to take place.