Some 80,000 dissertations and theses are currently added every year to the ProQuest collection from about 700 academic institutions from around the world through the ProQuest's Digital Archiving and Access Program that submit titles themselves. Dissertations since 1980 and Theses since 1988 include short abstracts written by the authors to include specific subject terms designed to enhance searchability. For titles not available in the ProQuest archive, the company does offer retrieval from partner institutions for a fee. The Full Text platform of ProQuest Dissertations and Theses provides 24-page previews of their stored titles. 

ProQuest Dissertations and Theses is a powerful tool for researching the unpublished, academic resources. The company maintains that its collection is indeed the most comprehensive in the world, and that ProQuest is the "official digital dissertations archive for the Library of Congress and the database of record for graduate research."  PQDT offers abstracting information as well as a rapidly growing body of full-text digitized materials, including "nearly 3 million searchable citations to dissertation and theses from around the world from 1743 to the present day together with over 1 million full-text dissertations that are available for download in PDF format. Over 2 million titles are available for purchase as printed copies. The database offers full text for most of the dissertations added since 1997 and strong retrospective full-text coverage for older graduate works."

The subscription search interface page permits multiple methods of searching, including of course by author and title, but also by institution, subject, language, and even advisor. As with other ProQuest products, in addition to altering the search parameters, patrons can also modify where the search is taking place. At the top of the page, one may select the databases being searched. For example, you may search Dissertations and Theses stricly in CIC institution, or choose to simultaneously search ProQuest UK and Ireland, Historical Newspapers, or many other ProQuest databases. 

There is also the possiblility to browse thousands of linked topics either by subject or by location, worldwide. By selecting "Browse" instead of Advanced or Basic Search. you can see thousands of linked subject titles organized alphabetically. If selecting the browse by location options, many countries of the world are accessible. It is possible to select further through the "+" in the left-hand box before the title. Doing this will pull up participating universities and academic institutions from the selected country, including showing you how many titles from that institution are accessible throug ProQuest.