A number of recent theses and dissertations prepared at Oxford are available to download from the Oxford Research Archive (ORA). The British Library provides access to UK theses through it's EThOS service. Already digitised UK theses can be downloaded freely as PDF files. Requests can be made to digitise older theses. The British Library no longer provides theses on microfilm.
Search for Oxford DPhil theses on SOLO by entering "thesis oxford" plus any keywords.
Science DPhil theses are held offsite and can be requested for consultation in the Radcliffe Science Library (RSL). All theses are for reference only.
More recent theses will also be available online via the Oxford Research Archive (ORA).