The Spring 1944 Modern Library catalog proclaimed the availability of the illustrated editions "containing the work of America's foremost living artists and book designers." At $1.50 for each boxed copy, it was a nickel more expensive than the giants and a whopping 55¢ (nearly two thirds!) more than the standard editions. It was an instant hit. In a March 1944 letter to his partner Donald Klopfer, who was fighting for the Allies in Europe at the time, Bennett Cerf wrote "The reception of the Illustrated Modern Library books is nothing less than ecstatic."
There were multiple printings of most titles; Shakespeare's Comedies, Shakespeare's Tragedies, Don Quixote, Famous Ghost Stories, and Walden were the only titles that had a single printing.
According to Barry Neavill, identifying a few of the first titles -- Holy Bible, Brothers Karamazov, Wisdom of Confucius, Pickwick Papers, and Tom Jones -- is simple: the words "Modern Library" instead of "Illustrated Modern Library" appear on both the spine and the title page. Proving the first edition status of the rest is pretty difficult.
Barry says this about how the Illustrated Modern Library ended: "Ten Illustrated ML titles were reprinted in 1947, mostly in printings of 5,000 or 6,000 copies. The acetate jackets had glued-on paper labels, which saved 4 or 5 cents a copy compared to silk screening. Only about half of each impression was bound. Some of the unbound copies ended up in regular Modern Library bindings and were sold with the regular series."
Gathered together below are all the illustrated editions in the ModernLib dust jacket database. Click 
under an image to see a small sample of that title's illustrations. Click the image itself to go to its author's page.
For a detailed list with data drawn from the BookList notations and other sources, see Guide to the Illustrated Editions. To see a list of books not in the illustrated series but which nonetheless had two or more illustrations, see Illustrated Unillustrateds.
