I found this book to be of tremendous help when choosing a Tabriz - Isfahan carpet. PRJ Ford gives a detailed summary of the regions and then discusses the individual designs. I found the knots per square meter to be very useful, thereby establishing the finer or coarser weave of the carpet. The author also comments on the influences the tribe and villagers at the time used in their carpets. The full colour layout of the photographs make it easy to identify the various carpets when thinking of buying. Very useful guide and a must to have.