AbstractOne of the problems that we experience with today's most widespread Internet Information Systems (like WWW or Gopher) is the lack of support for maintaining referential integrity. Whenever a resource is (re)moved, dangling references from other resources may occur.This paper presents a scalable architecture for automatic maintenance of referential integrity in large (thousands of servers) distributed information systems. A central feature of the proposed architecture is the p-flood algorithm, which is a scalable, robust, prioritizable, probabilistic server-server protocol for efficient distribution of update information to a large collection of servers.The p-flood algorithm is now implemented in the Hyper-G system, but may in principle also be implemented as an add-on for existing WWW and Gopher servers.Keywords: Hypertext, Link Consistency, Distributed Information System, Internet, Gopher, WWW, Hyper-G, Scalability, p-flood.