You should make your document set up with Facing Pages, not with single pages.
Thanks Willi. However, alot of these documents are from CS5 where it worked fine. I get them in from all over the place so don't set up the original files. Re-setting up in facing pages will take time....
I can't understand why it's worked in CS1-5 and now doesn't??
Maybe that your files have been set up correctly before?