The discovery of sound laws by comparing attested languages is the method which has unlocked the history of European languages stretching back thousands of years before the appearance of written records, e.g. Latin p- corresponds to English f- (pes, foot; primus, first; plenus, full). Although Burmese, Chinese, and Tibetan have long been regarded as related, the systematic exploration of their shared history has never before been attempted. Tracing the history of these three languages using just such sound laws, this book sheds light on the prehistoric language from which they descend. Written for readers with little linguistic knowledge of these languages, but fully explicit and copiously indexed for the specialist, this work will serve as the bedrock for future progress in the study of these languages.