Gmelin's Handbook of Inorganic Chemistry, presently comprising over 600 volumes, is the most comprehensive collection of chemical and physical data of the elements and their compounds in the world. It is Gmelin's first aim to assemble and systematically classify the research findings scattered throughout the innumerable publications of the international primary literature. The reduction of this mass of data into readily usable form combines exhaustive coverage of all published material, thorough and objective assessment of all results, strictly logical grouping of related facts, and modern monographic presentation. This vast amount of information is classified on the basis of the chemical elements, which in itself contributes to "user friendliness". A survey of the contents of the Handbook is given in the Complete Catalog (published every second year, with supplements in between), which can, thus, be very helpful when beginning a search. Access to a specific compound becomes even easier through consultation of the Formula Indexvolumes. For over three years the Gmelin Formula Index (plus the Complete Catalog entries) has been available as an online database, GFI, from STN. Online searches provide for a most comfortable and fast access to the Handbook. GFI is the first constituent of the complete Gmelin database presently under development. Subscribers to the Handbook are entitled to a 50 % discount when searching GFI online. Available free-of-charge: Gmelin Newsletter (2 issues/year) Gmelin Complete Catalog or Catalog Supplement brochures on special Handbook subjects Gmelin poster