The goal of this project is to develop a multimedia database management system with enhanced capabilities to handle heterogeneous monomedia queries and data. The development of this system caters to the computational and storage requirements while accommodating and exploiting the inevitable semantic and representational imprecisions inherent in such media. The underlying design philosophy of this system is based on multilevel data models and search mechanisms. These methodologies are designed to facilitate for the users the posing of various types of queries. These query types include the following: (1) low-level queries, such as finding objects in a multimedia database; (2) mid-level queries based on spatio-temporal semantics, such as locating events associated with multimedia data; and (3) high-level queries targeted towards searching pre-composed multimedia documents, based on constituent monomedia data, their spatio-temporal dimensions, and logical structure. The multi-level search mechanisms are tightly interlinked. Imprecision in the search results is modeled using a set of fuzzy parameters. The results of this research will provide a comprehensive framework for building wide variety of multimedia applications in commercial, educational, governmental and military sectors.