"Paul Frankl was, as Professor James S. Ackerman notes in his short but excellent introduction to this volume, one of the last survivors of the golden age of German art history. This book makes available in translation one of the most important of his works, a volume first published in 1914 and hitherto rather inaccessible to American scholars. A major reason for this inaccessibility—Frankl's difficult and often private language—has been eliminated by the superb translation of Professor James F. O'Gorman, who has also supplied a helpful set of notes. The book will be a welcome addition to any architectural library." —Leonard K. Eaton, Isis