The paper describes the results of the application of the "client–server" technology for the development of the Web version of the Historical Tsunami Database for the Pacific. The database consists of two main parts: the catalog of tsunamigenic events in the Pacific with their basis source parameters and the catalog of the observed or measured run-up heights at the coast. As a supplement part, the database contains the textual descriptions of tsunami manifestations, a set of digitized tsunami photos and some supporting information related to the tsunami problem (active tectonic faults, catalog of active volcanoes, list of mareograph stations, etc.). Currently, the event catalog contains 1447 tsunamigenic events occurred in the Pacific from 47 B.C. to the present time. The run-up catalog contains nearly 8000 coastal run-up observations and tide-gauge measurements provided with the geographical coordinates of sites. The Web version of the database is located on the server of the Tsunami Laboratory of the ICMMG SD RAS (http://tsbun.sscc.ru/htdbpac) in the Microsoft SQL Server 7.0 format that works under Windows NT Server 4.0 Service Pack 4, IIS 4.0. The client interface is written on Microsoft Visual InterDev 6.0 (ASP). The system is the platform independent (from the "client" part) and provides a remote user, who has the standard browser (Netscape 4.5 or Internet Explorer 4.0) and the network or modem connection to the Internet, with a certain set of function for the interaction with the database. Special screen forms were developed to provide a remote user with the possibility for data search by complex criteria, for data listing, sorting and for several types of data processing.