The Problem - Harmonic rhythm is one of those essential aesthetic aspects of traditional western harmony that begs for attention from scholars, demands to be taught to students, and yet frustrates teachers who attempt to explain it. The concept seems simple and a few well chosen examples can demonstrate its obvious importance, but analytical technique for harmonic rhythm has never had sufficient precision and consistency to be of much practical value since Walter Piston first defined the term in 1944. We have had precious little theory for it, and so no advice, no specifics such as those for voice leading, that we can give to our students. In the following pages I would like first to explain how a new analytical technique for harmonic rhythm called dimensional analysis can address these problems and second to describe my experience using this technique to teach harmonic rhythm in the second semester of a traditional harmony course. Dimensional analysis, the students agreed, provided a precise approach to harmonic rhythm that they could easily grasp, and at the same time amplified other fundamental aspects of harmonic practice by integrating them with rhythmic effects.