In his book, the author introduces and interprets the constitution, constitutional law and basic principles. In particular, constitutionalism, rule of law and democratic governance, its basic values as well as the principles and norms of separation of powers and balance of power have been presented in a logical manner. The feature of the book is to present the knowledge of the mentioned subject in simple language so that even the general reader can understand it. This book will be useful for anyone interested in constitutional law.