The new standard work on jazz harmony theory! Harmony theory is only valid if it serves ear training, as the analytical engagement with sounds should always aim for practical application. To avoid getting stuck in abstract theory, this new jazz harmony theory establishes a close relationship between theory, ear, and instrument. Musicians often struggle to find a balance among these three areas: too often, one encounters the virtuoso without personal charisma, the intellectual without playful intuition, and the passionate without instrumental skill. Therefore, this harmony theory does not solely address the intellect but also incorporates feeling and action into its considerations. Solutions to many exercises are available for free download. However, for didactic reasons, no solutions are provided for advanced exercises or tasks with specific relevance to practical playing.