This book investigates melodic transformations and melodic similarity. Here, melodic similarity is based upon the concept of melodic transformations. The relevant parameters are established based on the concept of intentionality. Then, melotonic, dynamic and chronotonic values are introduced. Subsequently, melotonic, dynamic and chronotonic transformations are developed. The algebraic structure of these transformations is investigated via reflection and translation matrices. Based on two specific reflections, the similarity and interval vectors are defined, which form the conceptual framework of melodic similarity. This is, the length of the similarity vector delivers information about how close two melodies are in absolute terms and the interval vector delivers the information about how similar two melodies are in terms of shape. The similarity and interval vectors form the basis for a variety of similarity models fashioned for specific contexts. The melotonic and chronotonic similarity model are put to their test in three experiments, with all there experiments in support of this approach.