If possible, it’s always a good idea to have your publisher selected before finalizing your color hard cover files. Though all cover art will need to allow for the thickness of the book board, as it folds around it and attaches to the inside (under the end sheets), variances in many other things will change the exact size and placement of elements on the cover layout. Additionally, even if returning to a publisher, don’t assume the cover process hasn’t altered in some way over time. For our current hard cover file information, visit http://www.gregthcompany.com/binding/art/hardcolorfiles.html