Subject directories and search engines are the most commonly used tools to search for information on the World Wide Web. We
propose a novel notion of subject meta-directory on top of standard subject directories, which strongly resembles the way
in which metasearch engines extend standard search engines. After analyzing the main choices arising in the design of subject
meta-directories, we describe the implementation of WebGate, a subject meta-directory entirely written in Prolog.
Keywords Prolog - Web-programming - subject directories