<p>My local library has most of the books I need for the AP exams but the problem is that all of them are old editions (from 1990-1998). In your experience, are older editions much different from new editions? I guess for subjects like history, there won't be much change?</p>
<p>Every now and then, the CollegeBoard decides to modify the composition of their tests (for example, the comparative government exam was changed very recently). It is for this reason that an old prep book might not reflect the focus of a newer exam. Do some research of your own about whether or not the exams you're interested have been modified, and if not, you should be fine with the old books.</p>
<p>But for sole review purposes, most old books (say 2002-2003) would be fine?</p>
<p>Yes, not much has changed since then.</p>