PROSPECTUS SUPPLEMENT

(To Prospectus dated November 13, 2006)

$543,767,100 (Approximate)

LEHMAN MORTGAGE TRUST

Mortgage Pass-Through Certificates, Series 2007-1

Lehman Brothers Holdings Inc.	Aurora Loan Services LLC
Sponsor and Seller	Master Servicer
Lehman Mortgage Trust 2007-1	Structured Asset Securities Corporation
Issuing Entity	Depositor


Consider carefully the risk factors beginning on page S-15 of this prospectus supplement and on page 6 of the prospectus. For a list of capitalized terms used in this prospectus supplement and the prospectus, see the glossary of defined terms beginning on page S-91 in this prospectus supplement and the index of principal terms on page 187 in the prospectus. The certificates will represent interests in the issuing entity only and will not represent interests in or obligations of the sponsor, the depositor or any of their affiliates or any other party. This prospectus supplement may be used to offer and sell the certificates only if accompanied by the prospectus.		The trust will provide for the issuance of: ● Twenty-four classes of senior certificates, including nine classes of interest-only certificates and seven classes of exchangeable securities. ● Eleven classes of subordinate certificates, including two classes of interest-only subordinate certificates. ● One additional class of certificates. The certificates represent ownership interests in a trust fund that consists primarily of three separate pools of mortgage loans. The classes of certificates offered by this prospectus and supplement are listed, together with their initial class principal amounts (or class notional amounts) and interest rates, under “The Offered Certificates” on page S-1 of this prospectus supplement. This prospectus supplement and the accompanying prospectus relate only to the offering of the certificates listed in the table on page S-1 and not to the other classes of certificates that will be issued by the trust fund as described in this prospectus supplement. Principal and interest on the offered certificates will be paid monthly. The first expected distribution date will be February 26, 2007. Credit enhancement for the offered certificates includes subordination, loss allocation and, for certain of the offered certificates, cross-collateralization features.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved the certificates or determined that this prospectus supplement or the accompanying prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

The certificates offered by this prospectus supplement will be purchased by Lehman Brothers Inc., as the underwriter, from Structured Asset Securities Corporation, and are being offered by Lehman Brothers Inc. from time to time for sale to the public in negotiated transactions or otherwise at varying prices to be determined at the time of sale. The underwriter has the right to reject any order. Proceeds to Structured Asset Securities Corporation from the sale of these certificates will be approximately 100.25% of their initial total principal amount, plus accrued interest, before deducting expenses.

On or about January 30, 2007, delivery of the certificates offered by this prospectus supplement, except the Class R Certificate, will be made through the book-entry facilities of The Depository Trust Company, Clearstream Banking Luxembourg and the Euroclear System, and delivery of the Class R Certificate will be made in physical form at the offices of Lehman Brothers Inc., New York, New York.

Underwriter:

LEHMAN BROTHERS

The date of this prospectus supplement is January 26, 2007

Important notice about information presented in this

prospectus supplement and the accompanying prospectus:

We provide information to you about the certificates offered by this prospectus supplement in two separate documents that progressively provide more detail: (1) the accompanying prospectus, which provides general information, some of which may not apply to your certificates and (2) this prospectus supplement, which describes the specific terms of your certificates.

The information presented in this prospectus supplement is intended to enhance the general terms of the accompanying prospectus. If the specific terms of this prospectus supplement and the general terms of the accompanying prospectus vary, you should rely on the information in this prospectus supplement.

You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not authorized anyone to provide you with different information.

We are not offering the certificates in any state where the offer is not permitted. We do not claim that the information in this prospectus supplement and prospectus is accurate as of any date other than the dates stated on their respective covers.

Dealers will deliver a prospectus supplement and prospectus when acting as underwriters of the certificates and with respect to their unsold allotments or subscriptions. In addition, all dealers selling the certificates will be required to deliver a prospectus supplement and prospectus for ninety days following the date of this prospectus supplement.

We include cross-references in this prospectus supplement and the accompanying prospectus to captions in these materials where you can find further related discussions. The following table of contents and the table of contents in the prospectus provide the pages on which these captions are located.

For European Investors Only

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a “Relevant Member State”), the underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the “Relevant Implementation Date”) it has not made and will not make an offer of certificates to the public in that Relevant Member State prior to the publication of a prospectus in relation to the certificates which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the competent authority in that Relevant Member State, all in accordance with the Prospectus Directive, except that it may, with effect from and including the Relevant Implementation Date, make an offer of certificates to the public in that Relevant Member State at any time: (a) to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities; (b) to any legal entity which has two or more of (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than €43,000,000 and (3) an annual net turnover of more than €50,000,000, as shown in its last annual or consolidated accounts; or (c) in any other circumstances which do not require the publication by the issuer of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of this provision, the expression an “offer of certificates to the public” in relation to any certificates in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the certificates to be offered so as to enable an investor to decide to purchase or subscribe the certificates, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression “Prospectus Directive” means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

S-ii

Tables of Contents

Prospectus Supplement

	Page
The Offered Certificates	S-1
Summary of Terms	S-3
Risk Factors	S-15
Glossary	S-26
Description of the Certificates	S-26
General	S-26
Book-Entry Registration	S-26
Priority of Distributions	S-27
Exchangeable Certificates	S-29
Distributions of Interest	S-30
Distribution of Prepayment Premium Amounts	S-32
Distributions of Principal	S-34
Cross-Collateralization	S-35
The Residual Certificate	S-36
Allocation of Realized Losses	S-36
Optional Purchase of the Mortgage Loans	S-38
Fees and Expenses of the Trust Fund	S-38
Description of the Mortgage Loans	S-39
The Mortgage Loans	S-39
Subgrouping/Collateral Groups	S-40
Collateral Group 1	S-41
Collateral Group 2A	S-41
Collateral Group 2B	S-41
Collateral Group 2C	S-42
Collateral Group 3A	S-42
Collateral Group 3B	S-42
Static Pool Information	S-43
Affiliations and Relationships	S-43
Origination of the Mortgage Loans and Underwriting Guidelines	S-44
Lehman Bank Underwriting Guidelines	S-46
IndyMac Bank Underwriting Guidelines	S-48
Additional Information	S-52
The Sponsor	S-53
The Depositor	S-53
The Master Servicer	S-53
The Servicers	S-53
General	S-53
Aurora Loan Services LLC	S-53
IndyMac Bank, F.S.B.	S-54
Administration of the Trust Fund	S-54
Servicing and Administrative Responsibilities	S-54
Trust Accounts	S-56
Example of Distributions	S-57
Mortgage Loan Servicing	S-59
General	S-59
Servicing Accounts and the Collection Account	S-59
Servicing Compensation and Payment of Expenses	S-60
Waiver or Modification of Mortgage Loan Terms	S-60
Prepayment Interest Shortfalls	S-60
Advances	S-61
Primary Mortgage Insurance	S-61
Collection of Taxes, Assessments and Similar Items	S-61
Insurance Coverage	S-61
Evidence as to Compliance	S-61
Master Servicer Default; Servicer Default	S-62
Amendment of the Servicing Agreements	S-62
Custody of the Mortgage Files	S-63
Special Servicer for Distressed Mortgage Loans	S-63
Pledge of Servicing Rights	S-63
Actions by the Sponsor and its Affiliates	S-63
Trust Agreement	S-64
General	S-64
The Issuing Entity	S-64
The Trustee	S-64
Assignment of Mortgage Assets	S-65
Representations and Warranties	S-66
Certain Matters Under the Trust Agreement	S-67
Reports to Certificateholders	S-71
Voting Rights	S-73
Yield, Prepayment and Weighted Average Life	S-73
General	S-73
Subordination of the Offered Subordinate Certificates	S-82
Weighted Average Life	S-83

S-iii

Material Federal Income Tax Considerations	S-84
General	S-84
Additional Considerations for the Class 2-A2, Class 2-A3, Class 2-A4, Class 3-A3 and Class 3-A4 Certificates	S-85
Residual Certificate	S-86
Additional Considerations for the Exchangeable Certificates	S-87
Legal Investment Considerations	S-87
ERISA Considerations	S-88
Use of Proceeds	S-89
Underwriting	S-89
Legal Matters	S-89
Ratings	S-89
Glossary of Defined Terms	S-91
Annex A: Global Clearance, Settlement and Tax Documentation Procedures	S-A-1
Annex B: Certain Characteristics of the Mortgage Loans	S-B-1
Annex C: Principal Amount Decrement Tables	S-C-1
Annex D: Available Exchange Combinations	S-D-1

S-iv

The Offered Certificates

The certificates consist of the classes of certificates listed in the tables below, together with the Class B7, Class B8, Class B9 and Class LT-R Certificates. Only the classes of certificates listed in the tables below are offered by this prospectus supplement.

Class	Collateral Group	Class Principal or Notional Amount⁽¹⁾	Initial Interest Rate⁽²⁾	Summary Interest Rate Formula	Summary Interest Rate Formula Subject to:			Initial Certificate Ratings⁽³⁾
Class	Collateral Group	Class Principal or Notional Amount⁽¹⁾	Initial Interest Rate⁽²⁾	Summary Interest Rate Formula	Minimum Rate	Maximum Rate	Principal Type	S&P	Fitch
1-A1	1	$15,462,000	5.7500%	5.7500%	Not Applicable	Not Applicable	Super Senior, Non-accelerating⁽⁵⁾	AAA	AAA
1-A2	1	$148,693,000	5.7500%	5.7500%	Not Applicable	Not Applicable	Senior, Sequential	AAA	AAA
1-A3	1	$1,060,000	5.7500%	5.7500%	Not Applicable	Not Applicable	Senior Support, Non-accelerating⁽⁵⁾	AAA	AAA
2-A1	2A, 2B, 2C	$281,561,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Senior, Exchangeable	AAA	AAA
2-A2⁽⁴⁾⁽⁷⁾	2B	$94,246,000⁽⁶⁾	1.3100%	6.6300% - LIBOR	0.0000%	6.6300%	Senior, Interest-Only	AAA	AAA
2-A3⁽⁴⁾⁽⁷⁾	2A	$134,273,000⁽⁶⁾	1.3100%	6.6300% - LIBOR	0.0000%	6.6300%	Senior, Interest-Only	AAA	AAA
2-A4⁽⁴⁾	2C	$72,242,000⁽⁶⁾	1.3100%	6.6300% - LIBOR	0.0000%	6.6300%	Senior, Interest-Only	AAA	AAA
2-A5	2A, 2B, 2C	$19,200,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Senior, Exchangeable	AAA	AAA
2-A6⁽⁴⁾	2A	$8,571,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Senior Support, Pass-Through	AAA	AAA
2-A7⁽⁴⁾	2A	$125,702,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Super Senior, Pass-Through	AAA	AAA
2-A8⁽⁴⁾	2B	$6,017,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Senior Support, Pass-Through	AAA	AAA
2-A9⁽⁴⁾	2B	$88,229,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Super Senior, Pass-Through	AAA	AAA
2-A10⁽⁴⁾	2C	$4,612,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Senior Support, Pass-Through	AAA	AAA
2-A11⁽⁴⁾	2C	$67,630,000	5.6900%	LIBOR + 0.3700%	0.3700%	7.0000%	Super Senior, Pass-Through	AAA	AAA
2-A12	2A, 2C	$206,515,000⁽⁶⁾	1.3100%	6.6300% - LIBOR	0.0000%	6.6300%	Senior, Exchangeable	AAA	AAA
2-A13	2A, 2B	$228,519,000⁽⁶⁾	1.3100%	6.6300% - LIBOR	0.0000%	6.6300%	Senior, Exchangeable	AAA	AAA
2-A14	2A, 2B, 2C	$300,761,000⁽⁶⁾	1.3100%	6.6300% - LIBOR	0.0000%	6.6300%	Senior, Exchangeable	AAA	AAA
3-A1	3A, 3B	$51,112,000	5.5700%	LIBOR + 0.2500%	0.2500%	7.5000%	Senior, Exchangeable	AAA	AAA
3-A2	3A, 3B	$51,112,000⁽⁶⁾	1.9300%	7.2500% - LIBOR	0.0000%	7.2500%	Senior, Exchangeable	AAA	AAA
3-A3⁽⁴⁾⁽⁷⁾	3B	$29,247,000⁽⁶⁾	1.9300%	7.2500% - LIBOR	0.0000%	7.2500%	Senior, Interest-Only	AAA	AAA
3-A4⁽⁴⁾⁽⁷⁾	3A	$21,865,000⁽⁶⁾	1.9300%	7.2500% - LIBOR	0.0000%	7.2500%	Senior, Interest-Only	AAA	AAA
3-A5⁽⁴⁾	3A	$21,865,000	5.5700%	LIBOR + 0.2500%	0.2500%	7.5000%	Senior, Pass-Through	AAA	AAA
3-A6⁽⁴⁾	3B	$29,247,000	5.5700%	LIBOR + 0.2500%	0.2500%	7.5000%	Senior, Pass-Through	AAA	AAA
B1	All	$13,752,000	6.2501%	Weighted Average Rate-0.4000%⁽⁸⁾	Not Applicable	Not Applicable	Subordinate	AA	AA
B2	All	$3,576,000	6.2501%	Weighted Average Rate-0.4000%⁽⁸⁾	Not Applicable	Not Applicable	Subordinate	N/R	AA-
BIO1	All	$17,328,000⁽⁶⁾	0.4000%	0.4000%	Not Applicable	Not Applicable	Subordinate, Interest-Only	N/R	AA-
B3	All	$4,126,000	6.4001%	Weighted Average Rate-0.2500%⁽⁸⁾	Not Applicable	Not Applicable	Subordinate	N/R	A
B4	All	$1,375,000	6.4001%	Weighted Average Rate-0.2500%⁽⁸⁾	Not Applicable	Not Applicable	Subordinate	N/R	A-
BIO2	All	$5,501,000⁽⁶⁾	0.2500%	0.2500%	Not Applicable	Not Applicable	Subordinate, Interest-Only	N/R	A-
B5	All	$2,750,000	6.6501%	Weighted Average Rate⁽⁸⁾	Not Applicable	Not Applicable	Subordinate	N/R	BBB
B6	All	$1,100,000	6.6501%	Weighted Average Rate⁽⁸⁾	Not Applicable	Not Applicable	Subordinate	N/R	BBB-
R	1	$100	5.7500%	5.7500%	Not Applicable	Not Applicable	Senior, Residual	AAA	AAA

(1)	These balances are approximate, as described in this prospectus supplement.

(2)	Reflects the initial interest rate as of the first distribution date.

(3)	The designation “N/R” means that the specified rating agency will not rate the certificates of that class.

(4)	These classes of certificates are Exchange Certificates. Certain combinations of Exchange Certificates can be exchanged for corresponding Exchangeable Certificates, as described in this prospectus supplement.

(5)	The Class 1-A1 and Class 1-A3 Certificates will not receive principal payments at the same rate as the other senior certificates because principal payments generally will not be distributable to the Class 1-A1 and Class 1-A3 Certificates until beginning with the distribution date in February 2012.

(6)

Initial notional amount. The Class 2-A2, Class 2-A3, Class 2-A4, Class 2-A12, Class 2-A13, Class 2-A14, Class 3-A2, Class 3-A3, Class 3-A4, Class BIO1 and Class BIO2 Certificates are interest-only certificates; they will not be entitled to payments of principal and will accrue interest on their notional amounts as described in this prospectus supplement.

(7)

The Class 2-A2, Class 2-A3, Class 3-A3 and Class 3-A4 Certificates will each be issued in two components: a Class I Component and a Class P Component, as described in this prospectus supplement. Each Class I Component will be issued with an interest-bearing component and will accrue interest at the rate described in the table above. Class P Components will not be issued with an interest rate or principal balance. The components are not severable.

(8)	The weighted average rate applicable to this formula will be based on the weighted average of the designated rate applicable to Collateral Groups 1, 2A, 2B, 2C, 3A and 3B, weighted on the basis of the group subordinate amounts thereof.

S-1

The offered certificates will also have the following characteristics:

Class	Record Date⁽¹⁾	Delay / Accrual Period⁽²⁾	Interest Accrual Convention	Final Scheduled Distribution Date⁽³⁾	Expected Final Distribution Date⁽⁴⁾	Minimum Denominations	Incremental Denominations	CUSIP Number
1-A1	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AA 5
1-A2	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AB 3
1-A3	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AC 1
2-A1	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AD 9
2-A2	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AE 7
2-A3	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AF 4
2-A4	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AG 2
2-A5	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AH 0
2-A6	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AJ 6
2-A7	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AK 3
2-A8	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AL 1
2-A9	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AM 9
2-A10	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AN 7
2-A11	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AP 2
2-A12	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AQ 0
2-A13	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AR 8
2-A14	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AS 6
3-A1	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AT 4
3-A2	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AU 1
3-A3	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AV 9
3-A4	DD	0 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F AW 7
3-A5	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AX 5
3-A6	DD	0 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AY 3
B1	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F AZ 0
B2	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F BA 4
BIO1	CM	24 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F BB 2
B3	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F BC 0
B4	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F BD 8
BIO2	CM	24 Day	30/360	2/25/2037	1/25/2037	$1,000,000	$1	52521F BE 6
B5	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F BF 3
B6	CM	24 Day	30/360	2/25/2037	1/25/2037	$ 100,000	$1	52521F BG 1
R	CM	24 Day	30/360	2/25/2037	2/25/2007	100%⁽⁵⁾	Not Applicable	52521F BH 9

(1)	CM = For any distribution date, the close of business on the last business day of the calendar month preceding the month of the related distribution date. DD = For any distribution date, the close of business on the business day immediately before that distribution date.

(2)

24 Day = For any distribution date, the interest accrual period will be the calendar month preceding that distribution date. 0 Day = For any distribution date, the interest accrual period beginning on the immediately preceding distribution date (or January 25, 2007, in the case of the first accrual period) and ending on the calendar day immediately before the related distribution date.

(3)	Calculated as described in this prospectus supplement.

(4)

The expected final distribution date, based upon (i) the applicable prepayment assumption and (ii) the modeling assumptions used in this prospectus supplement, each as described under “Yield, Prepayment and Weighted Average Life—Weighted Average Life.” The actual final distribution date for each class of offered certificates may be earlier or later, and could be substantially later, than the applicable expected final distribution date listed above.

(5)	The Class R Certificate will be issued in definitive, fully registered form, representing the entire percentage interest of that class.

S-2

Summary of Terms

This summary highlights selected information from this document and does not contain all of the information that you need to consider in making your investment decision. To understand all of the terms of the offering of the certificates, it is necessary that you read carefully this entire document and the accompanying prospectus.

While this summary contains an overview of certain calculations, cash flow priorities and other information to aid your understanding, you should read carefully the full description of these calculations, cash flow priorities and other information in this prospectus supplement and the accompanying prospectus before making any investment decision.

Some of the information that follows consists of forward-looking statements relating to future economic performance or projections and other financial items. Forward-looking statements are subject to a variety of risks and uncertainties, such as general economic and business conditions and regulatory initiatives and compliance, many of which are beyond the control of the parties participating in this transaction. Accordingly, what actually happens may be very different from the projections included herein.

Whenever we refer to a percentage of some or all of the mortgage loans in the trust fund or in a pool, that percentage has been calculated on the basis of the total scheduled principal balance of those mortgage loans as of January 1, 2007 in the trust fund or in a pool, as the context requires, unless we specify otherwise. We explain in this prospectus supplement under “Glossary of Defined Terms” how the scheduled principal balance of a mortgage loan is determined. Whenever we refer in this summary of terms or in the risk factors section of this prospectus supplement to the total principal balance of any mortgage loans, we mean the total of their scheduled principal balances, unless we specify otherwise.

Parties

Sponsor and Seller

Lehman Brothers Holdings Inc. will sell the mortgage loans to the depositor.

Depositor

Structured Asset Securities Corporation, a Delaware special purpose corporation, will sell the mortgage assets to the issuing entity. The depositor’s address is 745 7th Avenue, New York, New York, and its telephone number is (212) 526-7000.

Issuing Entity

Lehman Mortgage Trust 2007-1, a common law trust formed under the laws of the State of New York.

Trustee

Wells Fargo Bank N.A. will act as trustee for the trust.

Master Servicer

Aurora Loan Services LLC, an affiliate of Lehman Brothers Holdings Inc., the depositor and Lehman Brothers Inc., will oversee the servicing of mortgage loans by the primary servicer, but will not be ultimately responsible for the servicing of the mortgage loans except as described in this prospectus supplement.

S-3

Primary Servicers

On the closing date, Aurora Loan Services LLC and IndyMac Bank, F.S.B. will service approximately 36.63% and 63.37%, respectively, of the mortgage loans in the trust fund.

Subsequent to the closing date, primary servicing may be transferred to primary servicers other than the initial applicable servicer in accordance with the provisions of the trust agreement and the related servicing agreement, as described in this prospectus supplement.

See “The Servicers” and “Mortgage Loan Servicing” in this prospectus supplement for information regarding the servicers and servicing of the mortgage loans.

Originators

Approximately 36.63% and 63.37% of the mortgage loans in the trust fund were originated by Lehman Brothers Bank, FSB and IndyMac Bank, F.S.B., respectively.

See “Underwriting Guidelines” in this prospectus supplement for informaiton regarding the originators.

The Mortgage Loans

The certificates represent ownership interests in a trust fund, the assets of which will consist primarily of three pools of mortgage loans: “pool 1,” “pool 2” and “pool 3.” The pools were sorted, generally, on the basis of whether the related mortgage loans are subject to the payment of prepayment premium amounts in connection with any voluntary prepayments in full, and certain voluntary prepayments in part, made during varying periods after origination. Pool 1 will consist of mortgage loans that are subject to prepayment premium amounts in connection with any voluntary prepayments in full, and certain voluntary prepayments in part, regardless of whether such prepayments are made concurrently with the sale of the related mortgaged property. Pool 2 will consist of mortgage loans that are subject to prepayment premium amounts in connection with any voluntary prepayments in full, and certain voluntary prepayments in part, except when such prepayments are made concurrently with the sale of the related mortgaged property. Such prepayment premium amounts may be waived by the applicable servicer, or may be unenforceable, as described in this prospectus supplement under “Risk Factors — Special Risks for Special Classes of Certificates.” Pool 3 will consist of mortgage loans that are not subject to any prepayment premium amounts. The mortgage loans will have a total principal balance as of the cut-off date, which is January 1, 2007, of approximately $550,093,861.

The mortgage loans will be secured by mortgages, deeds of trust, or other security instruments, all of which are referred to in this prospectus supplement as mortgages. The mortgage loans in the trust fund will generally consist of fixed rate, conventional, fully amortizing and balloon, first lien residential mortgage loans.

S-4

Aggregate Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	2,508	—	—
Total Scheduled Principal Balance	$550,093,861	—	—
Scheduled Principal Balances	$14,972 to $1,750,000	$219,335	—
Mortgage Rates	6.250% to 9.375%	6.992%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	352 to 360	358	—
Original Loan-to-Value Ratios	5.36% to 100.00%	75.53%	—
Number of Interest Only Mortgage Loans	790	—	36.24%
Number of Balloon Mortgage Loans	195	—	8.65%
Geographic Distribution in Excess of 10.00% of the Total Scheduled Principal Balance:
California	532	—	29.67%
Florida	390	—	14.56%
Maximum Single Zip Code Concentration	1	—	0.32%
Credit Scores	604 to 819	703	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	2,025	—	77.55%

The mortgage loans are not insured or guaranteed by any government agency.

See “Description of the Mortgage Pool” in this prospectus supplement and “The Trust Funds—The Mortgage Loans” in the prospectus for a general description of the mortgage loans.

None of the mortgage loans in the trust fund will be “high-cost loans” under applicable federal, state or local anti-predatory or anti-abusive lending laws.

Collateral Groups

In order to facilitate the structuring of the certificates, each mortgage loan, or a specified portion thereof, has been assigned to one or more “collateral groups” based on the mortgage loan’s net mortgage rate. Each collateral group, in turn, has been designed to support the payment of a separate group of certificates (identified in the table on page S-1). For example, Collateral Group 1 has been assembled by allocating specified portions of certain loans (based on allocation percentages described in this prospectus supplement) such that the collateral group will produce interest at an annual rate of 5.75%; amounts received on the collateral group will be applied on each distribution date to pay the related senior certificates which bear interest at a blended rate of 5.75% per annum. Because amounts from a collateral group will be distributed to the related certificate group, the payment experience of any collateral group will determine the rate of payments on the certificates.

“Collateral Group 1” consists of mortgage loans in pool 1, pool 2 and pool 3 or portions thereof that have been stripped to a net mortgage rate of 5.75%. “Collateral Group 2A” consists of mortgage loans in pool 1 or portions thereof that have been stripped to a net mortgage rate of 7.00%. “Collateral Group 2B” consists of mortgage loans in pool 2 or portions thereof that have been stripped to a net mortgage rate of 7.00%. “Collateral Group 2C” consists of mortgage loans in pool 3 or portions thereof that have been stripped to a net mortgage rate of 7.00%. “Collateral Group 3A” consists of mortgage loans in pool 1 or portions thereof that have been stripped to a net mortgage rate of 7.50%. “Collateral Group 3B” consists of mortgage loans in pool 2 or portions thereof that have been stripped to a net mortgage rate of 7.50%.

The collateral groups are expected to have the following characteristics:

S-5

Collateral Group 1 Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	1,744	—	—
Total Contributed Principal Balance	$175,759,977	—	—
Scheduled Principal Balances	$14,972 to $1,750,000	$251,975	—
Mortgage Rates	6.250% to 8.900%	6.680%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	352 to 360	358	—
Original Loan-to-Value Ratios	5.36% to 100.00%	72.95%	—
Number of Interest Only Mortgage Loans	582	—	37.74%
Number of Balloon Mortgage Loans	140	—	8.64%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
California	467	—	39.90%
Florida	243	—	10.50%
Maximum Single Zip Code Concentration	5	—	0.58%
Credit Scores	620 to 819	710	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	1,306	—	73.46%

Collateral Groups 2A, 2B and 2C Combined Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	2,390	—	—
Total Contributed Principal Balance	$319,959,298	—	—
Scheduled Principal Balances	$14,972 to $1,750,000	$217,739	—
Mortgage Rates	6.250% to 9.375%	7.038%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	352 to 360	358	—
Original Loan-to-Value Ratios	5.36% to 100.00%	75.97%	—
Number of Interest Only Mortgage Loans	766	—	36.52%
Number of Balloon Mortgage Loans	189	—	8.88%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
California	522	—	27.12%
Florida	366	—	15.60%
Maximum Single Zip Code Concentration	1	—	0.49%
Credit Scores	620 to 819	702	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	1,907	—	75.98%

S-6

Collateral Group 2A Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	1,103	—	—
Total Contributed Principal Balance	$142,843,962	—	—
Scheduled Principal Balances	$14,972 to $850,000	$225,035	—
Mortgage Rates	6.250% to 8.375%	6.937%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	352 to 360	358	—
Original Loan-to-Value Ratios	5.36% to 100.00%	73.61%	—
Number of Interest Only Mortgage Loans	354	—	36.00%
Number of Balloon Mortgage Loans	82	—	8.24%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
California	339	—	35.39%
Florida	208	—	18.16%
New York	84	—	10.63%
Maximum Single Zip Code Concentration	3	—	0.64%
Credit Scores	620 to 819	692	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	1,103	—	100.00%

Collateral Group 2B Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	804	—	—
Total Contributed Principal Balance	$100,262,057	—	—
Scheduled Principal Balances	$41,424 to $744,358	$193,103	—
Mortgage Rates	6.250% to 9.375%	7.249%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	352 to 360	358	—
Original Loan-to-Value Ratios	16.00% to 100.00%	81.33%	—
Number of Interest Only Mortgage Loans	264	—	39.16%
Number of Balloon Mortgage Loans	21	—	2.79%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
Florida	132	—	19.22%
California	90	—	16.05%
Maximum Single Zip Code Concentration	3	—	0.79%
Credit Scores	620 to 814	710	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	804	—	100.00%

S-7

Collateral Group 2C Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	483	—	—
Total Contributed Principal Balance	$76,853,278	—	—
Scheduled Principal Balances	$47,000 to $1,750,000	$243,604	—
Mortgage Rates	6.250% to 8.050%	6.950%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	352 to 360	358	—
Original Loan-to-Value Ratios	12.82% to 100.00%	73.37%	—
Number of Interest Only Mortgage Loans	148	—	34.04%
Number of Balloon Mortgage Loans	86	—	17.99%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
California	93	—	26.20%
Maximum Single Zip Code Concentration	1	—	2.05%
Credit Scores	620 to 817	710	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	0	—	0.00%

Collateral Groups 3A and 3B Combined Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	595	—	—
Total Contributed Principal Balance	$54,374,584	—	—
Scheduled Principal Balances	$37,043 to $799,435	$159,451	—
Mortgage Rates	7.350% to 9.375%	7.726%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	353 to 360	358	—
Original Loan-to-Value Ratios	12.40% to 100.00%	81.25%	—
Number of Interest Only Mortgage Loans	159	—	29.74%
Number of Balloon Mortgage Loans	34	—	7.39%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
Florida	111	—	21.56%
Texas	100	—	12.81%
California	40	—	11.58%
Maximum Single Zip Code Concentration	1	—	1.47%
Credit Scores	604 to 812	687	—
Number of Mortgage Loans with Prepayment Premium Amounts at Origination	595	—	100.00%

S-8

Collateral Group 3A Mortgage Loan Summary

	Range or Total	Weighted Average	Total Percentage
Number of Mortgage Loans	260	—	—
Total Contributed Principal Balance	$23,260,808	—	—
Scheduled Principal Balances	$37,043 to $446,317	$161,859	—
Mortgage Rates	7.350% to 8.375%	7.603%	—
Original Terms to Maturity (in months)	360	—	—
Remaining Terms to Maturity (in months)	353 to 360	358	—
Original Loan-to-Value Ratios	12.40% to 100.00%	78.77%	—
Number of Interest Only Mortgage Loans	67	—	31.66%
Number of Balloon Mortgage Loans	27	—	13.38%
Geographic Distribution in Excess of 10.00% of the Total Contributed Principal Balance:
Florida	52	—	22.06%
California	20	—	11.04%
Maximum Single Zip Code Concentration	1	—	1.55%
Credit Scores	620 to 801