World-Wide Web is a media where information is unstructured, distributed, multimedia and multilingual Many tools have been developed to help users search for information: subject hierarchies, general search engines, browsers and search assistants. Although helpful, they show serious limitations, mainly in terms of precision, multilingual indexing and distribution. The M.A.R.V.I.N project (Multi Agent Retrieval Vagabond on Information Networks) proposes solutions with a distribution of the indexing task in agents specialized in a given domain. M.A.R.V.I.N has been successfully applied to the medical domain. The medical index and its associated search engine MedHunt (Medical Hunter) demonstrate the interest of such an approach with currently 50,000 indexed medical sites and more than 100,000 accesses each month.