November 14, 2005 Mail Stop 4561 By U.S. Mail and facsimile to (312) 630-6739 William A. Osborn Chief Executive Officer Northern Trust Corporation Fifty South LaSalle Street Chicago, IL 60675 	Re:	Northern Trust Corporation 		Form 10-K for Fiscal Year Ended December 31, 2004 		Filed March 14, 2005 		File No. 0-05965 Dear Mr. Osborn: 	We have reviewed your response letter dated September 27, 2005 and have the following additional comments. Financial Statements Note 18 - Other Operating Income and Expenses, page 83 1. We note your response to comment 1 from our letter dated September 13, 2005. Please revise future filings to provide the disclosures required by paragraph 23 with respect to your direct-finance leases. 2. Please revise future filings to disclose the components of your investment in leveraged leases as set forth in paragraph 43 of SFAS 13. * * * * Please respond to this comment within 10 business days or tell us when you will provide us with a response. Your letter should key your responses to our comment and provide any requested information. Please file your letter on EDGAR. Please understand that we may have additional comments after reviewing your responses to our comments. You may contact Isa Farhat at (202) 551-3485 or me at (202) 551-3246 if you have questions regarding our comments. Sincerely, 						Angela Connell 						Senior Accountant William A. Osborn Northern Trust Corporation November 11, 2005 Page 1