A talented violinist as well as a painter, Klee drew much of the inspiration for his abstract art from musical rhythms and structure. Like a composer, he developed and harmonized pictorial themes, weaving a complex series of signs and symbols into his painting. In this book, the art historian Hajo Duechting focuses his study primarily on Klee's decade-long tenure at the Bauhaus, where the artist's theories and practice first merged, and where he was to develop his Colour Spectrum, Square and Polyphone painting series. Illustrated throughout with full-colour reproductions of Klee's paintings and etchings, as well as entries from his diaries, this study aims to shed light on an important aspect of Klee's work, while providing insights into his development as an abstract artist.