Joseph Zawinul is arguably one of the more interesting cultural figures of the 20th century, perhaps the only non-American to have a profound effect on the music that we call jazz. Author Brian Glasser argues that this book is a "portrait" rather than a biography, aiming for emotional truth over factual specificity. Whatever the intent, the book views Zawinul very much through the prism of his music with the emphasis on the subject's musical career and very little on his life beyond music making. It is not an authorized biography in the sense of after giving Glasser several interviews, Zawinul apparently withdrew his cooperation, forcing Glasser to cobble together much of the book from previously published interviews and accounts. The result is a certain unevenness to the story - aspects of Zawinul's childhood are covered in a fair amount of detail, but in contrast it is only mentioned in passing that at a certain point Zawinul was married and had a family; later, we again learn in passing that his wife is named Maxine, that she is African-American, similarly the names of their children crop up sort of randomly etc.
In some respects this is not a major drawback - the emphasis is rightly on Zawinul's music, and many (most?) readers will already be acquainted with the basic facts of his life. Yet, it would appear to be an extraordinary life, and it is a pity that it is not the subject of a more polished biography.