A document management and thumbnail image viewing system enables a user to display separate pages in individual different documents as well as to expand an image to view more detail in a single document, move pages across documents, and insert/delete pages or documents. A document management and viewing system includes a user interface for providing data representing a single composite display image including multiple reduced size images of individual pages of a first document and multiple reduced size images of individual pages of a different second document. The single composite display image includes at least one indicator identifying a transition between pages of the first and second documents and enables a user to select and move a page from the first document to the second document. A document processor updates stored data representing the first and second documents in response to a command entered using the single composite display image.