This is a superbly illustrated book with good colour reproductions of most iconic works. The text is also strong: its a thoughtful study of the works of art for themselves, not a biography. Barbara Hess does a sterling job of introducing the artist's perplexing compositions and labyrinthine ideas for uninitiated readers - she summarises critical debates over Johns in the period 1955-65 very well. Her stress is on explaining, frequently using comments by Johns himself to help us come to grips with the pictures.
Still, the book is chiefly about Johns's output of the 1950s and early 1960s. The coverage of this period takes up the first 52 pages, or roughly 3½ of her book's 5 chapters. Which means that the discussion of Johns's work produced over 1967-2001 is compressed: the discussion of these late decades speeds along, cramming in information. So the reader needs to turn to specialist books and exhibition catalogues for that material.
Nevertheless, as an introduction for the novice or student, this is a fine work (and a bargain at its affordable price, too).
I bought this book to help me with my art project. This was very useful in giving information on the art works themselves as well as the artist. I would recommend this book, especially if you are interested in art.