The goal of the Tsimmis Project is to develop tools that facilitate the rapid integration of heterogeneous information sources that may include both structured and unstructured data. This paper gives an overview of the project, describing components that extract properties from unstructured objects, that translate information into a common object model, that combine information from several sources, that allow browsing of information, and that manage constraints across heterogeneous sites. Tsimmis is a joint project between Stanford and the IBM Almaden Research Center. 1 Overview A common problem facing many organizations today is that of multiple, disparate information sources and repositories, including databases, object stores, knowledge bases, file systems, digital libraries, information retrieval systems, and electronic mail systems. Decision makers often need information from multiple sources, but are unable to get and fuse the required information in a timely fashion due to the diffculties of accessing the different systems, and due to the fact that the information obtained can be inconsistent and contradictory. Research sponsored by the Wright Laboratory, Aeronautical Systems Center, Air Force Material Command, USAF, under Grant Number F33615-93-1-1339. The US Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation thereon. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the offcial policies or endorsements, either express or implied, of Wright Laboratory or the US Government. This work was also supported by the Reid and Polly Anderson Faculty Scholar Fund, the Center for Integrated Systems at Stanford University, and by Equipment Grants from Digital Equipment Corporation and IBM Corporation. The goal of the TSIMMIS 1 project is to provide tools for accessing, in an integrated fashion, multiple informati
