This paper discusses the role of intelligent agents in facilitating the seeking and retrieval of information in Web-based library environments. An overview is presented on agents and their current application in library domains to produce a generic agent-based model for libraries to follow. The model suggests that Web-based information seeking and retrieval in library contexts could be enhanced through a collaborating network of interface and information agents. Recent research results offer insights on the design of interface agents to support Web-based browsing and searching. These are applied to the model in terms of the functionality required to facilitate information seeking and retrieval behaviour across library collections. Implications on library policy and digital collections surrounding the use of agents are also discussed.