This paper starts with a brief description of what a database is followed by a short history of the development of the database system and its use; it also notes the proliferation of various kinds of databases in the 1990s. It then goes on to outline the background of establishing a Pearl River Delta Collection at the City University of Hong Kong and the Hong Kong Lingnan College. One of the tasks in this project is to build up a database of Pearl River Delta-related materials available in all the UPGC(University and Polytechnic Grant Committee)libraries in Hong Kong. The database design and structure are described, and the problems associated with data collection, source data, and updating together with their solutions are explained.