**Exhibit 35 a)**[Aurora Loan Services Logo] Depositor:  Structured Asset Securities Corporation                    745 Seventh Avenue, 8th Floor                      New York, NY 10019 Trustee:      US Bank, N.A.                      One Federal Street, 3rd Floor                    Boston, MA 02110 Securities Administrator:   Subject: Annual Officer's Certification Fiscal Year: 2006 Securitization: LXS 2006-18N I, E. Todd Whittemore, the undersigned, a duly authorized officer of Aurora Loan Services LLC (the "Master Servicer"), do certify the following for the Calendar Year 2006: 1.    A review of the activities of the Master Servicer during the preceding calendar year (or portion thereof) and of its performance under the Agreement for such period has been made under my supervision. 2.     To the best of my knowledge, based on such review, the Master Servicer has fulfilled all of its obligations under the Agreement in all material aspects throughout 2006 (or applicable portion thereof), or, if there has been a failure to fulfill any such obligation in any material respect, I have specifically identified to  the  Depositor, and the Trustee each such failure known to me and the nature and status thereof, including the steps being taken by the Master Servicer to remedy such default. Certified by:  AURORA LOAN SERVICES LLC By: /s/  E. Todd Whittemore Name:  E. Todd Whittemore Title:    Executive Vice President **b)********Countrywide****HOME LOANS**400 Countrywide Way  Simi Valley. California 93065-6298  Februaiy 28, 2007 Aurora Loan Services LLC  10350 Park Meadows Drive  Littleton, CO 80124  OFFICERS CERTIFICATE  I, Joseph Candelario, hereby certify & that I am an officer of Countrywide OP, Inc., general partner of Countrywide Home Loans Servicing LP (the "Servicer"). I further certify, with respect to the applicable servicing agreement relating to the securitization transaction(s) set forth on Exhibit A attached hereto (the "Servicing Agreement") that:  (a) A review of the activities of the Servicer during the preceding calendar year and of the performance of the Servicer under the Servicing Agreement has been made under my supervision; and  (b) To the best of my knowledge, based on such review, the Servicer has fulfilled all of its obligations under the Servicing Agreement in all material respects throughout such year.  ***Joseph Candelario******February 28, 2007*First Vice President  Compliance Officer  Loan Administration  See Deal Name listing on following page. Exhibit A  LMT 2006-9  LXS 2006-17  LXS 2006-19  LXS 2006-12N  LXS 2006-16N  LXS 2006-18N**c)**Indymac LOGO **REG AB 1123 Statement of Compliance******I am an authorized officer for IndyMac Bank, F.S.B, the servicer for the transactions listed on the attached schedule and I certify:  a)   A review of IndyMac Bank's activities during the reporting period and of its  performance under the applicable servicing agreement has been made under my                                                                 supervision.  b)   To the best of my knowledge, based on such review, except as set forth below  IndyMac Bank has fulfilled all of its obligations under the agreement in all material  respects throughout the reporting perio d.  c)    None  By: /s/ Robert M. Abramian            Robert M. Abramian            First Vice President             Home Loans Servicing             Investor Reporting             Indymac Bank   By: /s/ Bart Vincent Bart Vincent  First Vice President  HLS-Finance  Financial  Indymac Bank  Prepared for:     Aurora Loan Services  Date:      February 28, 2007  Ref:   EXHIBIT A  www.indymac.com 7700 W. Parmer Lane, Bldg D, Austin TX 78729 **********************EXHIBIT A******137     LXS 2006-12N LB 7/27/06  139     LXS2006-11 7/27/06  140     LMT 2006-4 7/28/06  187     ITF SARM 2006-8 (LB) 8/31/06  188     LXS 2006-14N (LB) 8/31/06  193     ITF LXS 2006-13 8/31/06  234     ITF SARM 2006-4 04/28/06  238     LXS 2006-7 04/28/06  276     ITF LXS 2006-8 05/31/06  286     ITF LXS 2006-1 ON (6-30-06)  294     LMT 2006-5 8-31-06  374     ITF LXS 2006-16N 092906  377     ITF LXS 2006-15 092906  433     LMT 2006-6 09/29/06  441     ITF LXS 2006-17 10/30/06  443     LMT 2006-7 10/30/06  447     LXS2006-18N 11/29/2006  448     LXS2006-19 11/29/2006  449     LMT 2006-8 11/29/2006  903     ITF LXS 2006-2N 1/31/06  4108   LMT 2006-9 12/29/06  4109   LXS2006-20 12/29/06**d)**[GMAC LOGO] SERVICER COMPLIANCE STATEMENT (Item 1123)  Residential Funding Company, LLC  Lehman XS Trust, Series 2006-18N (the "Issuing Entity")  The undersigned, a duly authorized officer****of Residential Funding Company, LLC (formerly Residential Funding Corporation), as servicer (the "Servicer"), does hereby certify that: 1. A review of the Servicer's activities during the period covered by the Issuing Entity's report on Form 10-K and of the Servicer's performance under the applicable servicing agreement has been made under my supervision.  2. To the best of my knowledge, based on such review, the Servicer has fulfilled all of its obligations under the applicable servicing agreement in all material respects throughout such period.  IN WITNESS WHEREOF, the undersigned has duly executed this Certificate this 6th day of  March2007. By: [Signature] Name: Anthony N. Renzi  Title: Managing Director ****