On Line Theses
The British Library EThOS service aims to offer a 'single point of access' where researchers the world over can access ALL theses produced by participating UK Higher Education institutions. Access them from ethos.bl.uk and, should researchers request theses from your institution, you will be requested to send them to The British Library for digitisation.
Dart-Europe E Theses is a partnership of research libraries and library consortia who are working together to improve global access to European research theses. To search their database go to http://www.dart-europe.eu/basic-search.php
Hard Copy Theses
A useful, regularly updated document, that includes lending policies for hard copy theses from academic libraries has also been compiled by Graham Titley, University of Plymouth on behalf of the Forum for Interlending.