The National Library of Medicine has decided to discontinue the printing of the Index Medicus Supplement, sometimes known as the Black and White MeSH. We have received a great number of comments on this proposal, and are grateful for the input. Overall, it appears that our impression that few would be inconvenienced by the discontinuation of the printed edition was correct. Given the high cost of printing even a few copies of the book, we do not see the benefit as justifying the expense. For those wishing a souvenir copy, the 2007 MeSH will continue to be available from the Government Printing Office for another 14 months. In response to concerns expressed by several individuals, we plan to make available a set of PDF files containing the various hierarchies. These will be formatted in such a way as to make printing them on 81/2 by 11 inch paper feasible, enabling a user to print out and review an entire tree easily. We encourage all to avail themselves of the resources available at www.nlm.nih.gov/mesh. There is a considerable amount of printable introductory material, information about how we update MEDLINE, as well as links to downloable files and the MeSH browser. The PDF files of the trees will also be available there. The current MeSH files are available for download, in one of three different formats. Furthermore, the browser at the MeSH website provides ready access to the current version of MeSH. The browser supports partial word searches of three letters or more, and provides many links between related terms. As is our practice, all of these services and files will remain free of charge. Once again, we wish to express our gratitude for the many comments received. Stuart J. Nelson, MD Head, Medical Subject Headings 8600 Rockville Pike Building 38A Room B2 E17 301-496-1495 (Office) 301-402-2002 (Fax) "The limits of my language mean the limits of my world."