ProQuest is comprised of a number of constituent sub-databases, all of which are searched simultaneously. It is, however, possible to specify the databases to be searched by selecting from the multiple databases list.
One of the principal component databases making up ProQuest is Digital Dissertations, which can be searched separately through the link on the library's home page.
For a comparable and complementary database, see Academic Search Premier, accessible from the Databases list on our library's homepage; see the Knowledge Base article for more information on this resource. Columbia University Libraries subscribe to Academic Search Complete, a database from the same producer (Ebsco) with significantly more extensive coverage than Academic Search Premier.