Exhibit 4.15  


        THIS
SUPPLEMENT, dated as of January 20, 2005, (this "Supplement"), is to the Security Agreement, dated as of March 17, 2004 (as amended, supplemented, amended and restated
or otherwise modified from time to time, the "Security Agreement"), among the Grantors (such capitalized term, and other terms used in this Supplement, to have the meanings set forth or incorporated
by reference in Article I of the Security Agreement) from time to time party thereto, in favor of The Bank of New York Trust Company, N.A., in its capacity as the First Priority Agent. 


W I T N E S S E T H:  


        WHEREAS, the Eschelon Operating Company has entered into an Indenture, dated as of the date hereof (as amended, supplemented, amended and restated or otherwise
modified from time to time, the "Indenture") with The Bank of New York Trust Company, N.A., as Trustee (in such capacity, the "Trustee"), pursuant to which it has issued, as of the date hereof,
83/8% Senior Second Secured Notes due 2010 in the original aggregate principal amount of $165,000,000; 



        WHEREAS,
pursuant to the provisions of the Indenture and Section 7.11 of the Security Agreement, the undersigned is becoming a Grantor under the Security Agreement; 


        NOW,
THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned agrees, for the benefit of the Collateral Agent, the
Trustee and the Holders, as follows. 


        SECTION 1. Party to Security Agreement, Etc.    By its signature below the undersigned hereby agrees to become a Grantor under
the Security Agreement and hereby assumes the Obligations of a Grantor thereunder, with the same force and effect as if it were an original signatory thereto. The undersigned Grantor hereby
(a) agrees to be bound by and comply with all of the terms and provisions of the Security Agreement applicable to it as a Grantor and (b) represents and warrants that the representations
and warranties made by it as a Grantor thereunder are true and correct as of the date hereof, unless stated to relate solely to an earlier date, in which case, such representations and warranties
shall be true and correct in all material respects as of such earlier date. In furtherance of the foregoing, each reference to a "Grantor" in the Security Agreement shall be deemed to include the
undersigned Grantor. Attached to this Supplement are the various Schedules required under the terms of the Security Agreement, accurately completed by an Authorized Officer of the Grantor. 



        SECTION 2. Full Force of Security Agreement.    Except as expressly supplemented hereby, the Security Agreement shall remain in
full force and effect in accordance with its terms. 


        SECTION 3. Governing Law, Entire Agreement, Etc.    THIS SUPPLEMENT SHALL BE DEEMED TO BE A CONTRACT MADE UNDER AND GOVERNED BY
THE INTERNAL LAWS OF THE STATE OF NEW YORK (INCLUDING FOR SUCH PURPOSE SECTIONS 5-1401 AND 5-1402 OF THE GENERAL OBLIGATIONS LAW OF THE STATE OF NEW YORK). THIS SUPPLEMENT AND
THE OTHER LOAN DOCUMENTS CONSTITUTE THE ENTIRE UNDERSTANDING AMONG THE PARTIES HERETO WITH RESPECT TO THE SUBJECT MATTER HEREOF AND THEREOF AND SUPERSEDE ANY PRIOR AGREEMENTS, WRITTEN OR ORAL, WITH
RESPECT THERETO. 


        SECTION 4. Counterparts.    This Supplement may be executed by the parties hereto in several counterparts, each of which shall
be deemed to be an original and all of which shall constitute together but one and the same agreement. Delivery of an executed counterpart of a signature page to this Security Agreement by facsimile
shall be effective as delivery of a manually executed counterpart of this Security Agreement. 


*
* * * * 









        IN
WITNESS WHEREOF, the undersigned Grantor has caused this Supplement to be duly executed and delivered by its Authorized Officer as of the date first above written. 



	

SHARED COMMUNICATIONS SERVICES, INC.	
 	

 
	

By:	

/s/ Geoffrey M. Boyd
 Geoffrey M. Boyd

Chief Financial Officer	
 	

 
	

Accepted by:	
 	

 
	

THE BANK OF NEW YORK TRUST COMPANY, N.A., as Collateral Agent
	

By:	

/s/ Patrick T. Giordano
 Patrick T. Giordano

Vice President	
 	

 









SCHEDULE I

to Supplement No. 4

to Security Agreement

(Shared Communications Services, Inc.)  


Item A. Locations of Grantor:  


Oregon 


Item B. Filing locations last five years  



N/A. 


Item C. Trade names  


Shared
Communications Systems, Inc. 


Item D. Merger or other corporate reorganization  



None. 


Item E. Taxpayer ID numbers  


93-0914013 


Item F. Government Contracts  


None. 


Item G. Deposit Accounts  


None.








SCHEDULE II

to Supplement No. 4

to Security Agreement

(Shared Communications Services, Inc.)  



Item A. Patents  


None. 


Issued Patents:    None. 


Item B. Patent Licenses  


None. 







SCHEDULE III

to Supplement No. 4

to Security Agreement

(Shared Communications Services, Inc.)  


Item A. Trademarks  


None.



Registered Trademarks:    None. 


Pending Trademark Applications:    None. 



Trademark Applications in Preparation:    None. 


Item B. Trademark Licenses  


None.








SCHEDULE IV

to Supplement No. 4

to Security Agreement

(Shared Communications Services, Inc.)  


Item A. Copyrights/Mask Works  


Registered
Copyrights/Mask Works:    None. 


Copyright/Mask Work Pending Registration Applications:    None. 



Copyright/Mask Work Registration Applications in Preparation:    None. 


Item B. Copyright/Mask Work Licenses  


None.








SCHEDULE V

to Supplement No. 4

to Security Agreement

(Shared Communications Services, Inc.)  


Trade Secret or Know-How Licenses  


None.