Most Postgraduate dissertations are now digitised and can be accessed via the Middlesex University Research Repository, which is an searchable database of research produced by staff and researchers at Middlesex University, open and freely accessible to the research community and public.
There are several ways for you to obtain a thesis from another univeristy for your research.
EThOS is a scheme run by the British Library - search their catalogue first to see if the thesis you need has already been digitised.
You will need to register in order to download theses as PDFs - you can also opt to pay to have a copy printed for you.
If the thesis hasn't already been digitised through EThOS, you may order it as an inter-library loan. If you are a distance learner then contact the Distance Learner Library Support for more information. Each inter-library loan request will cost £3.
From the other institution
If you can visit the other library, this is often the quickest way of accessing theses. You may need a SCONUL card.
Check their library catalogue to see if they hold a copy of the thesis you need. Theses are not usually on the open shelves, so check to see how long it will take - you may have to order it several days in advance.