This book investigates the historical evolution and technical application of tempo rubato, a fundamental yet often misunderstood expressive device in Western music. Richard Hudson, a scholar of musicology, utilizes an extensive array of primary source documents, including treatises from theorists and personal writings from composers and performers, to categorize rubato into two distinct historical types. By mapping these variations from the era of Gregorian Chant through the twentieth century, Hudson provides a rigorous framework for understanding how rhythmic flexibility has been employed across diverse musical periods and styles.

Experts recognize this work as a definitive reference for the study of rhythmic performance practice in Western music. Readers frequently note the academic density of the prose and the meticulous nature of the historical research presented.