Digital libraries are organized, focused collections of information. They are focused on a particular topic or theme—and good digital libraries will articulate the principles governing what is included. They are organized to make information accessible in particular, well-defined, ways—and good ones will include a description of how the information is organized (Lesk, 1997). The Greenstone digital library software is intended to help users construct simple collections of information very quickly. Indeed, only a few minutes of the user's time are needed to set up a collection based on a standard design and initiate the building process. Collections may be large—some comprise Gbytes of text; millions of documents. Furthermore, even larger vo...