With many of our books, we use a process called Smyth sewing for the binding. Smyth sewing is basically the same process that has been used for years and years to professionally bind most if not all hard cover books. Pull any of your fine art coffee table books from your bookshelf and nine times out of ten, they'll be bound using this process.
The way the Smyth sewing works is we take several sheets of paper, fold them in half, and sew from the middle fold through the rest of the pages into the binding. This bunch of paper is called a signature.

To make a book, several signature are then sewn together to form the block, or as I like to call it: the guts. The guts are then mounted into casing or the outside cover via the end-sheets.

The end-sheets are generally blank or colored pages, although several of our styles do have printed end-sheets. The sheets are first mounted to the inside cover and are then mounted to the first and last signatures of the book.
To ensure that the books last a lifetime, the first and last signatures have to have a certain number of pages to give enough strength to the binding and end-sheets. Because of this, occasionally additional blank pages are added to the end of the book which gives that final signature the number of pages needed.
I do get the question as to where the sweet spots are to minimize any blank pages in the book. The signatures are in sets of 16, and we need two blanks at the end for the mounting. Although the calculation isn't too bad, I've attached a spreadsheet with all of the number crunching/page counting already done. On it I've listed the page counts versus the number of blank pages at the end, and have highlighted the sweet spots :)
SignaturePageCount_current.xls (30.5 KB)
The Smyth process does take a bit longer is more labor intensive than some styles of binding (hand sewing, lining up every page perfectly, etc), but it's well worth it for the flexiblity and durability it gives the books.
It's this binding that lets the books lay flat for a superior presentation of your images, and allows us to offer a lifetime guarantee on the binding of every book in the Couture Collection!