The book explores the unique constitutional model in operation in Thailand. Utilising the concept of 'mixed constitutional monarchy', it investigates the hybridised semi-authoritarian, semi-liberal monarchy that exists in Thailand. It goes further to show the institutionalised nature of the Thai monarchy by studying its constitutional texts in light of local doctrine. These findings challenge commonly accepted claims about Thailand, arguing that any political and constitutional instability is not the result of its borrowing from Western constitutionalism, as generally thought. Rather, it shows that the monarchy's use of constitutionalism is the prime driver of that instability. Drawing on materials and sources not previously available in English, this important work provides a comprehensive and critical account of the Thai 'mixed constitutional monarchy' from its origins to the present day.