UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-K

(Mark One)
|X| ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT
OF 1934 For the fiscal year ended: December 31, 2007
                                       or
|_| TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES
   EXCHANGE ACT OF 1934
For the transition period ______________________________


             Commission file number of issuing entity: 333-131209-14
                           RASC SERIES 2007-KS1 TRUST
           (Exact name of issuing entity as specified in its charter)

                    RESIDENTIAL ASSET SECURITIES CORPORATION
              (Exact name of depositor as specified in its charter)

                        RESIDENTIAL FUNDING COMPANY, LLC
               (Exact name of sponsor as specified in its charter)

                                    New York
      (State or other jurisdiction of incorporation or organization of the
                                 issuing entity)

            c/o Residential Funding Company, LLC, as Master Servicer
                        One Meridian Crossings, Suite 100
                          Minneapolis, Minnesota 55423
           (Address of principal executive offices of issuing entity)

             (952) 857-7000 (Telephone number, including area code)

                                      None
                      (I.R.S. Employer Identification No.)

                                       N/A
           (Former name, former address, if changed since last report)

Securities registered pursuant to Section 12(b) of the Act: None
Securities registered pursuant to Section 12(g) of the Act: None
Indicate by check mark if the  registrant is a well-known  seasoned  issuer,  as
defined in Rule 405 of the Securities Act.
Yes |_|  No  |X|


<PAGE>


Indicate  by  check  mark if the  registrant  is not  required  to file  reports
pursuant to Section 13 or Section 15(d) of the Act.
Yes |X|  No  |_|
Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements  for the past 90 days.
|X| Yes |_| No
Indicate by check mark if disclosure of delinquent  filers  pursuant to Item 405
of Regulation  S-K (ss.  229.405 of this chapter) is not contained  herein,  and
will not be  contained,  to the best of  registrant's  knowledge,  in definitive
proxy or  information  statements  incorporated  by reference in Part III of the
Form 10-K or any amendment to this Form 10-K. |X|
[Item 405 of Regulation S-K is not applicable.]

Indicate by check mark whether the registrant is a large  accelerated  filer, an
accelerated filer, a non-accelerated  filer, or a smaller reporting company. See
the definitions of "large accelerated  filer,"  "accelerated filer" and "smaller
reporting company" in Rule 12b-2 of the Exchange Act. (Check one):
Large accelerated filer  |_|                              Accelerated filer  |_|
Non-accelerated filer    |X| (Do not check if a smaller reporting company)
                                                  Smaller reporting company  |_|

Indicate by check mark whether the  registrant is a shell company (as defined in
Rule 12b-2 of the Act).
Yes |_|  No  |X|
Registrant  has no  voting  or  non-voting  common  equity  outstanding  held by
non-affiliates.


<PAGE>


                                     PART I

THE FOLLOWING ITEMS HAVE BEEN OMITTED IN ACCORDANCE  WITH GENERAL  INSTRUCTION J
TO FORM 10-K:

Item 1:  Business.
Item 1A: Risk Factors.
Item 2:  Properties.
Item 3:  Legal Proceedings.
Item 4:  Submission of Matters to a Vote of Security Holders.

ITEM 1B. UNRESOLVED STAFF COMMENTS.

Not Applicable.

SUBSTITUTE INFORMATION PROVIDED IN ACCORDANCE WITH GENERAL INSTRUCTION J TO FORM
10-K:

ITEM 1112(B) OF REGULATION AB. SIGNIFICANT OBLIGORS OF POOL ASSETS
(FINANCIAL INFORMATION).

None.

ITEM 1114(B)(2) OF REGULATION AB: CREDIT ENHANCEMENT AND OTHER SUPPORT,
EXCEPT FOR CERTAIN DERIVATIVES INSTRUMENTS (FINANCIAL INFORMATION).

None.

ITEM 1115(B) OF REGULATION AB: CERTAIN DERIVATIVES INSTRUMENTS
(FINANCIAL INFORMATION).

Based  on the  standards  set  forth  in  Item  1115(b)  of  Regulation  AB,  no
information is required in response to this Item.

ITEM 1117 OF REGULATION AB: LEGAL PROCEEDINGS.

There are no material pending legal or other proceedings  involving the mortgage
loans or Residential Funding Company,  LLC ("Residential  Funding"),  as sponsor
and master servicer,  Residential  Asset Securities  Corporation,  as depositor,
RASC Series 2007-KS1 Trust, as the issuing entity, GMAC Mortgage, LLC ("GMACM"),
as subservicer,  or other parties  described in Item 1117 of Regulation AB that,
individually  or in the  aggregate,  would  have a  material  adverse  impact on
investors in the securities (the "Securities") to which this report relates.


<PAGE>


Residential Funding and GMACM are currently parties to various legal proceedings
arising from time to time in the ordinary  course of their  businesses,  some of
which purport to be class actions. Based on information currently available,  it
is the opinion of Residential Funding and GMACM that the eventual outcome of any
currently pending legal proceeding,  individually or in the aggregate,  will not
have a material adverse effect on their ability to perform their  obligations in
relation to the mortgage  loans.  No assurance,  however,  can be given that the
final outcome of these legal proceedings, if unfavorable, either individually or
in the  aggregate,  would not have a  material  adverse  impact  on  Residential
Funding  or GMACM.  Any such  unfavorable  outcome  could  adversely  affect the
ability of  Residential  Funding or GMACM to perform its  servicing  duties with
respect  to the  mortgage  loans  and  potentially  lead to the  replacement  of
Residential Funding or GMACM with a successor servicer.

Among  the  legal  proceedings  to  which  Residential  Funding  is a party is a
putative class action lawsuit that was filed against a lender (Mortgage  Capital
Resources Corporation),  Residential Funding and other parties in state court in
Kansas City,  Missouri.  Plaintiffs  asserted  violations of the Missouri Second
Mortgage  Loan Act  ("SMLA"),  Mo.R.S.  Section  408.233,  based on the lender's
charging or  contracting  for payment of allegedly  unlawful  closing  costs and
fees.  The relief sought  included a refund of all allegedly  illegal fees,  the
refund of interest paid, and the discounted present value of interest to be paid
in the future on active mortgage loans.  The plaintiffs also sought  prejudgment
interest and punitive damages.

Residential  Funding is an assignee of some of the  mortgage  loans in question.
The plaintiffs  contended that  Residential  Funding is strictly  liable for the
lender's alleged SMLA violations pursuant to the assignee provisions of the Home
Ownership  and Equity  Protection  Act of 1994,  15 U.S.C.  Section  1641(d)(1).
Residential  Funding  terminated its  relationship  with the lender in early May
2000.

In connection with that  proceeding,  on January 4, 2008, a verdict was returned
that Residential  Funding pay $4.33 million in actual damages and $92 million in
punitive damages.  Residential  Funding intends to appeal and vigorously contest
the punitive  damage award.  However,  even if the punitive  damage award is not
reduced  upon  appeal,   Residential  Funding's  management  believes  that  any
liability  with  respect to this  proceeding  would not have a material  adverse
effect on investors in the Securities.


<PAGE>


                                     PART II

THE FOLLOWING ITEMS HAVE BEEN OMITTED IN ACCORDANCE  WITH GENERAL  INSTRUCTION J
TO FORM 10-K:

Item 5:  Market for Registrant's Common Equity, Related Stockholder
         Matters and Issuer Purchases of Equity Securities.
Item 6:  Selected Financial Data.
Item 7:  Management's Discussion and Analysis of Financial Condition and
         Results of Operations.
Item 7A: Quantitative and Qualitative Disclosures About Market Risk.
Item 8:  Financial Statements and Supplementary Data.
Item 9:  Changes in and Disagreements With Accountants on Accounting
         and Financial Disclosure.
Item 9A: Controls and Procedures.

ITEM 9B: OTHER INFORMATION.

None.

                                    PART III

THE FOLLOWING ITEMS HAVE BEEN OMITTED IN ACCORDANCE  WITH GENERAL  INSTRUCTION J
TO FORM 10-K:

Item 10: Directors and Executive Officers of the Registrant.
Item 11: Executive Compensation.
Item 12: Security Ownership of Certain Beneficial Owners and Management
         and Related Stockholder Matters.
Item 13: Certain Relationships and Related Transactions.
Item 14: Principal Accountant Fees and Services.

SUBSTITUTE INFORMATION PROVIDED IN ACCORDANCE WITH GENERAL INSTRUCTION J TO FORM
10-K:

ITEM 1119 OF REGULATION AB:  AFFILIATIONS AND CERTAIN RELATIONSHIPS AND
RELATED TRANSACTIONS.

Information  contemplated  by Item 1119 of  Regulation  AB has been omitted from
this report in reliance on the Instruction to Item 1119.

ITEM 1122 OF REGULATION AB: COMPLIANCE WITH APPLICABLE SERVICING
CRITERIA.

Each of Residential Funding, GMACM,  Homecomings Financial, LLC ("Homecomings"),
U.S. Bank National Association and Wells Fargo Bank, National Association (each,
a "Servicing  Participant")  has been  identified  by the  registrant as a party
participating in the servicing  function with respect to the pool assets held by
the Issuing Entity.  Reports  assessing  compliance with the servicing  criteria
applicable to each Servicing  Participant  (each, a "Report on Assessment")  are
attached as exhibits  to this Form 10-K.  In  addition,  an  attestation  report
(each,  an  "Attestation  Report")  regarding each Report on Assessment has been
prepared by the related Servicing  Participant's  registered  independent public
accounting firm and is attached as an exhibit to this Form 10-K.


<PAGE>


Residential  Capital,  LLC,  which  owns  indirectly  all of the  equity of both
Homecomings and GMACM, has restructured the operations of Homecomings and GMACM.
As a result of the restructuring -

   (i) on May 1, 2007, the computer system on which  Homecomings  maintained its
      servicing  platform  was  transferred  from one system  (LSAMS) to another
      system (MortgageServ) on which its affiliate GMACM maintains its servicing
      platform; and

   (ii) on September 24, 2007,  Homecomings  transferred its servicing  platform
      and certain employees responsible for the servicing function to GMACM.

Since  September  24, 2007,  GMACM has serviced the mortgage  loans owned by the
trust that were  previously  serviced by  Homecomings,  and  Homecomings has not
serviced any of those mortgage loans.

As a result of the integration of the Homecomings and GMACM servicing  platforms
on a single computer system as described in clause (i) above -

   (x) the Report on Assessment and related Attestation Report filed as Exhibits
      33.3 and 34.3 to this Form 10-K address  Homecomings'  compliance with the
      applicable servicing criteria for the pre-platform integration period from
      January 1, 2007 through April 30, 2007; and

   (y) the Report on Assessment and related Attestation Report filed as Exhibits
      33.2 and 34.2 to this Form 10-K  address (1) GMACM's  compliance  with the
      applicable servicing criteria for the pre-platform integration period from
      January 1, 2007 through April 30, 2007, and (2) each of  Homecomings'  and
      GMACM's  compliance  with  the  applicable   servicing  criteria  for  the
      post-platform  integration  period from May 1, 2007  through  December 31,
      2007.

Vendors

A Servicing  Participant may engage one or more vendors to perform  specific and
limited,  or scripted  activities  that  address all or a portion of one or more
servicing criteria applicable to such Servicing Participant. In general in these
cases,  the Servicing  Participant  has  instituted  policies and  procedures to
monitor whether such vendors'  activities  comply in all material  respects with
such  servicing  criteria,  and may elect to take  responsibility  for assessing
compliance with the servicing criteria applicable to such vendors' activities in
such  Servicing   Participant's  Report  on  Assessment.   Where  the  Servicing
Participant  has not  instituted  such  policies  and  procedures,  or where the
Servicing  Participant  does  not  otherwise  elect to take  responsibility  for
assessing its vendors'  activities,  the vendor is itself treated as a Servicing
Participant  and is required to provide its own Report on Assessment and related
Attestation Report.


<PAGE>


Exceptions

Except as disclosed below, no Report on Assessment or related Attestation Report
has identified  (i) any material  instance of  noncompliance  with the servicing
criteria  identified  in such Report on  Assessment as applicable to the related
Servicing  Participant  or  (ii)  any  material  deficiency  in  such  Servicing
Participant's policies and procedures to monitor vendor compliance.

GMAC Mortgage,  LLC: The Report on Assessment  prepared by GMACM and the related
Attestation Report have identified  material  noncompliance with two elements of
one servicing criterion applicable to it. Specifically, with regard to servicing
criterion 1122(d)(2)(vii),  which contemplates that reconciliations are prepared
on a monthly basis for all asset-backed securities related bank accounts -

   o  certain  custodial  account  reconciliations  were not reviewed within the
      timelines outlined in GMACM's policies and procedures,  as contemplated by
      criterion 1122(d)(2)(vii)(C); and

   o  certain  custodial  accounts had reconciling items which were not resolved
      within 90 calendar days of original  identification,  as  contemplated  by
      criterion 1122(d)(2)(vii)(D).

The registrant  does not believe these instances of  noncompliance  had material
impacts or effects on  investors,  and  appropriate  measures have been taken to
resolve the bank reconciliation items noted in the Report on Assessment,  and to
prevent such instances of  noncompliance in the future or to detect them in such
a manner as to permit prompt correction.

Homecomings Financial, LLC: The Report on Assessment prepared by Homecomings and
the related Attestation Report have identified  material  noncompliance with one
servicing  criterion  applicable to it.  Specifically,  with regard to servicing
criterion  1122(d)(4)(x)(C),  certain refunds resulting from payoff transactions
were not returned to the obligor  within 30 calendar  days of full  repayment of
the related pool asset, as  contemplated by such criterion.  The registrant does
not believe these instances of noncompliance  had material impacts or effects on
investors, and appropriate measures have been taken to prevent such instances of
noncompliance  in the  future  or to  detect  them in such a manner as to permit
prompt correction.

Platform-Level Reports

Regulations of the Securities and Exchange  Commission  (the "SEC") require that
each  Servicing  Participant  complete a Report on  Assessment  at a  "platform"
level,  meaning that the transactions covered by the Report on Assessment should
include  all  asset-backed  securities  transactions  involving  such  Servicing
Participant  that are backed by the same asset type.  Further  guidance from the
SEC staff identifies  additional  parameters  which a Servicing  Participant may
apply to define  and  further  limit its  platform.  For  example,  a  Servicing
Participant  may define its  platform  to include  only  transactions  that were
completed  on or after  January  1, 2006 and that were  registered  with the SEC
pursuant  to  the  Securities  Act  of  1933.  Each  Servicing   Participant  is
responsible  for defining its own platform,  and each  platform  will  naturally
differ based on various factors,  including the Servicing Participant's business
model,  the  transactions  in which it is involved  and the range of  activities
performed in those transactions.


<PAGE>


Based on our understanding of their platforms and the guidance that is available
at this time, we believe that the parameters by which the Servicing Participants
have defined their platforms should be permissible.  However,  because the SEC's
regulations  are new and the guidance  that is available at this time is subject
to clarification or change, we cannot assure you that the SEC and its staff will
necessarily agree.

ITEM 1123 OF REGULATION AB: SERVICER COMPLIANCE STATEMENT.

Each of Residential Funding, GMACM and Homecomings (each, a "Servicer") has been
identified by the  registrant as a servicer with respect to the pool assets held
by the Issuing Entity. Each Servicer has provided a statement of compliance with
its  obligations  under the servicing  agreement  applicable to such Servicer (a
"Compliance  Statement") for the portion of the period covered by this Form 10-K
during which such Servicer was servicing the pool assets, in each case signed by
an authorized officer of such Servicer. Each Compliance Statement is attached as
an exhibit to this Form 10-K.  None of the Compliance  Statements has identified
any instance  where the related  Servicer has failed to fulfill its  obligations
under the applicable servicing agreement in any material respects.

                                     PART IV

ITEM 15.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES.

      (a)(1) Not Applicable.

      (a)(2) Not Applicable.

      (a)(3) Not Applicable.

      (b)    Exhibits.

EXHIBIT
NUMBER                                  DESCRIPTION
----------   ------------------------------------------------------------------
3.1          Certificate  of  Incorporation  of  Residential   Asset  Securities
             Corporation (incorporated by reference to the Annual Report on Form
             10-K for the period ended  December 31, 2006,  filed by RASC Series
             2006-KS1 Trust with the Securities and Exchange Commission).


<PAGE>


3.2          Bylaws of Residential Asset Securities Corporation (incorporated by
             reference  to the Annual  Report on Form 10-K for the period  ended
             December 31,  2006,  filed by RASC Series  2006-KS1  Trust with the
             Securities and Exchange Commission).
10.1         Pooling and Servicing  Agreement dated as of January 1, 2007 by and
             among  Residential  Asset  Securities  Corporation,  as  depositor,
             Residential Funding Company, LLC, as master servicer, and U.S. Bank
             National  Association,  as trustee  (incorporated  by  reference to
             Exhibit  10.1  included  in the  Report  on Form  8-K  filed by the
             Issuing Entity with the Securities and Exchange Commission on March
             14, 2007).
10.2         Assignment and Assumption Agreement,  dated as of February 8, 2007,
             between  Residential  Funding  Company,  LLC and Residential  Asset
             Securities  Corporation  (incorporated by reference to Exhibit 10.2
             included in the Report on Form 8-K filed by the Issuing Entity with
             the Securities and Exchange Commission on February 23, 2007).
10.3         SB-AM Swap  Confirmation,  dated as of February 8, 2007,  between
             U.S. Bank National  Association,  as supplemental  interest trust
             trustee  for the  benefit of RASC  Series  2007-KS1  Supplemental
             Interest   Trust,    acting   on   behalf   of   the   Class   SB
             Certificateholders,   and  U.S.  Bank  National  Association,  as
             supplemental  interest  trust  trustee  for the  benefit  of RASC
             Series 2007-KS1  Supplemental Interest Trust, acting on behalf of
             the Class A Certificateholders and the Class M Certificateholders
             (incorporated by reference to Exhibit 10.3 included in the Report
             on Form 8-K filed by the Issuing  Entity with the  Securities and
             Exchange Commission on February 23, 2007).
10.4         Swap Confirmation,  dated as of February 8, 2007, between U.S. Bank
             National  Association,  as  supplemental  interest trust trustee on
             behalf of the RASC Series 2007-KS1 Supplemental Interest Trust, and
             Bear Stearns Financial Products Inc.  (incorporated by reference to
             Exhibit  10.4  included  in the  Report  on Form  8-K  filed by the
             Issuing  Entity with the  Securities  and  Exchange  Commission  on
             February 23, 2007).
10.5         Cap Confirmation,  dated as of February 8, 2007,  between U.S. Bank
             National  Association,  as  supplemental  interest trust trustee on
             behalf of the RASC Series 2007-KS1 Supplemental Interest Trust, and
             Bear Stearns Financial Products Inc.  (incorporated by reference to
             Exhibit  10.5  included  in the  Report  on Form  8-K  filed by the
             Issuing  Entity with the  Securities  and  Exchange  Commission  on
             February 23, 2007).
10.6         Class A  Corridor  Confirmation,  dated  as of  February  8,  2007,
             between U.S. Bank National  Association,  as supplemental  interest
             trust  trustee on behalf of the RASC Series  2007-KS1  Supplemental
             Interest   Trust,   and  Bear  Stearns   Financial   Products  Inc.
             (incorporated  by reference to Exhibit 10.6  included in the Report
             on Form 8-K filed by the  Issuing  Entity with the  Securities  and
             Exchange Commission on February 23, 2007).
10.7         Class  M/Class B Corridor  Confirmation,  dated as of  February  8,
             2007,  between U.S.  Bank  National  Association,  as  supplemental
             interest  trust  trustee  on  behalf  of the RASC  Series  2007-KS1
             Supplemental  Interest Trust, and Bear Stearns  Financial  Products
             Inc.  (incorporated  by reference  to Exhibit 10.7  included in the
             Report on Form 8-K filed by the Issuing  Entity with the Securities
             and Exchange Commission on February 23, 2007).


<PAGE>


10.8         ISDA Master  Agreement,  ISDA Schedule to the Master  Agreement and
             ISDA  Credit  Support  Annex to the  Schedule  to the  ISDA  Master
             Agreement,  all dated as of February  8, 2007,  between  U.S.  Bank
             National  Association,  as  supplemental  interest trust trustee on
             behalf of the RASC Series 2007-KS1 Supplemental Interest Trust, and
             Bear Stearns Financial Products Inc.  (incorporated by reference to
             Exhibit  10.8  included  in the  Report  on Form  8-K  filed by the
             Issuing  Entity with the  Securities  and  Exchange  Commission  on
             February 23, 2007).
31.1         Certification of Residential Funding Company,  LLC pursuant to Rule
             13a-14(d)/15d-14(d) under the Securities Exchange Act of 1934.
33.1         Report on  Assessment  of  Compliance  with  Servicing  Criteria of
             Residential  Funding  Company,  LLC as of and for the period  ended
             December 31, 2007.
33.2         Report on Assessment of Compliance  with Servicing  Criteria of (i)
             GMAC Mortgage,  LLC for the  pre-platform  integration  period from
             January  1,  2007  through  April  30,  2007,   and  (ii)  each  of
             Homecomings   Financial,   LLC  and  GMAC  Mortgage,  LLC  for  the
             post-platform  integration period from May 1, 2007 through December
             31, 2007.
33.3         Report on  Assessment  of  Compliance  with  Servicing  Criteria of
             Homecomings Financial,  LLC for the pre-platform integration period
             from January 1, 2007 through April 30, 2007.
33.4         Report on Assessment of Compliance with Servicing  Criteria of U.S.
             Bank National  Association  as of and for the period ended December
             31, 2007.
33.5         Report on Assessment of Compliance with Servicing Criteria of Wells
             Fargo Bank,  National  Association  as of and for the period  ended
             December 31, 2007.
34.1         Attestation Report of  PricewaterhouseCoopers  LLP on Assessment of
             Compliance with Servicing Criteria relating to Residential  Funding
             Company, LLC.
34.2         Attestation Report of  PricewaterhouseCoopers  LLP on Assessment of
             Compliance with Servicing  Criteria relating to GMAC Mortgage,  LLC
             and Homecomings Financial, LLC (filed as Exhibit 33.2 hereto).
34.3         Attestation Report of  PricewaterhouseCoopers  LLP on Assessment of
             Compliance   with  Servicing   Criteria   relating  to  Homecomings
             Financial, LLC (filed as Exhibit 33.3 hereto).
34.4         Attestation Report of Ernst & Young LLP on Assessment of
             Compliance with Servicing Criteria relating to U.S. Bank
             National Association.
34.5         Attestation Report of KPMG LLP on Assessment of Compliance with
             Servicing Criteria relating to Wells Fargo Bank, National
             Association.
35.1         Servicer Compliance Statement of Residential Funding Company,
             LLC.
35.2         Servicer Compliance Statement of GMAC Mortgage, LLC.
35.3         Servicer Compliance Statement of Homecomings Financial, LLC.

      (c) Not Applicable.


<PAGE>


                                   SIGNATURES

Pursuant to the  requirements of Section 13 or 15(d) of the Securities  Exchange
Act of 1934,  the  registrant  has duly  caused  this report to be signed on its
behalf by the undersigned, thereunto duly authorized.

Date:  March 24, 2008
                                        RASC SERIES 2007-KS1 TRUST

                                        By:  Residential Funding
                                             Company, LLC,
                                             as Master Servicer

                                        By: /s/ Anthony N. Renzi
                                            Name:  Anthony N. Renzi
                                            Title: Managing Director
                                            (senior officer in charge of
                                            the servicing function)


<PAGE>


                              INDEX TO EXHIBITS

Exhibit
Number                                  Description
----------   ------------------------------------------------------------------
3.1          Certificate of Incorporation of Residential Asset Securities
             Corporation  (incorporated by reference to the Annual Report on
             Form 10-K for the period ended December 31, 2006, filed by RASC
             Series 2006-KS1 Trust with the   Securities and Exchange
             Commission).
3.2          Bylaws of Residential Asset Securities Corporation (incorporated
             by reference  to the Annual Report on Form 10-K for the period
             ended December 31, 2006,  filed by RASC Series 2006-KS1 Trust
             with the Securities and Exchange Commission).
10.1         Pooling and Servicing Agreement dated as of January 1, 2007 by
             and among Residential Asset Securities Corporation, as
             depositor, Residential Funding Company, LLC, as master servicer,
             and U.S. Bank National Association, as trustee (incorporated by
             reference to Exhibit 10.1 included in the Report on Form 8-K
             filed by the Issuing Entity with the Securities and Exchange
             Commission on March 14, 2007).
10.2         Assignment and Assumption Agreement, dated as of February 8,
             2007, between Residential Funding Company, LLC and Residential
             Asset Securities Corporation (incorporated by reference to
             Exhibit 10.2 included in the Report on Form 8-K filed by the
             Issuing Entity with the Securities and Exchange Commission on
             February 23, 2007).
10.3         SB-AM Swap Confirmation, dated as of February 8, 2007, between
             U.S. Bank National Association, as supplemental interest trust
             trustee for the benefit of RASC Series 2007-KS1 Supplemental
             Interest Trust, acting on behalf of the Class SB
             Certificateholders, and U.S. Bank National Association, as
             supplemental interest trust trustee for the benefit of RASC
             Series 2007-KS1 Supplemental Interest Trust, acting on behalf of
             the Class A Certificateholders and the Class M
             Certificateholders (incorporated by reference to Exhibit 10.3
             included in the Report on Form 8-K filed by the Issuing Entity
             with the Securities and Exchange Commission on February 23,
             2007).
10.4         Swap Confirmation, dated as of February 8, 2007, between U.S.
             Bank National Association, as supplemental interest trust
             trustee on behalf of the RASC Series 2007-KS1 Supplemental
             Interest Trust, and Bear Stearns Financial Products Inc.
             (incorporated by reference to Exhibit 10.4 included in the
             Report on Form 8-K filed by the Issuing Entity with the
             Securities and Exchange Commission on February 23, 2007).
10.5         Cap Confirmation, dated as of February 8, 2007, between U.S.
             Bank National Association, as supplemental interest trust
             trustee on behalf of the RASC Series 2007-KS1 Supplemental
             Interest Trust, and Bear Stearns Financial Products Inc.
             (incorporated by reference to Exhibit 10.5 included in the
             Report on Form 8-K filed by the Issuing Entity with the
             Securities and Exchange Commission on February 23, 2007).


<PAGE>


10.6         Class A Corridor Confirmation, dated as of February 8, 2007,
             between U.S. Bank National Association, as supplemental interest
             trust trustee on behalf of the RASC Series 2007-KS1 Supplemental
             Interest Trust, and Bear Stearns Financial Products Inc.
             (incorporated by reference to Exhibit 10.6 included in the
             Report on Form 8-K filed by the Issuing Entity with the
             Securities and Exchange Commission on February 23, 2007).
10.7         Class M/Class B Corridor Confirmation, dated as of February 8,
             2007, between U.S. Bank National Association, as supplemental
             interest trust trustee on behalf of the RASC Series 2007-KS1
             Supplemental Interest Trust, and Bear Stearns Financial Products
             Inc. (incorporated by reference to Exhibit 10.7 included in the
             Report on Form 8-K filed by the Issuing Entity with the
             Securities and Exchange Commission on February 23, 2007).
10.8         ISDA Master Agreement, ISDA Schedule to the Master Agreement and
             ISDA Credit Support Annex to the Schedule to the ISDA Master
             Agreement, all dated as of February 8, 2007, between U.S. Bank
             National Association, as supplemental interest trust trustee on
             behalf of the RASC Series 2007-KS1 Supplemental Interest Trust,
             and Bear Stearns Financial Products Inc. (incorporated by
             reference to Exhibit 10.8 included in the Report on Form 8-K
             filed by the Issuing Entity with the Securities and Exchange
             Commission on February 23, 2007).
31.1         Certification of Residential Funding Company, LLC pursuant to
             Rule 13a-14(d)/15d-14(d) under the Securities Exchange Act of
             1934.
33.1         Report on Assessment of Compliance with Servicing Criteria of
             Residential Funding Company, LLC as of and for the period ended
             December 31, 2007.
33.2         Report on Assessment of Compliance with Servicing Criteria of
             (i) GMAC Mortgage, LLC for the pre-platform integration period
             from January 1, 2007 through April 30, 2007, and (ii) each of
             Homecomings Financial, LLC and GMAC Mortgage, LLC for the
             post-platform integration period from May 1, 2007 through
             December 31, 2007.
33.3         Report on Assessment of Compliance with Servicing Criteria of
             Homecomings Financial, LLC for the pre-platform integration
             period from January 1, 2007 through April 30, 2007.
33.4         Report on Assessment of Compliance with Servicing Criteria of
             U.S. Bank National Association as of and for the period ended
             December 31, 2007.
33.5         Report on Assessment of Compliance with Servicing Criteria of
             Wells Fargo Bank, National Association as of and for the period
             ended December 31, 2007.
34.1         Attestation Report of PricewaterhouseCoopers LLP on Assessment
             of Compliance with Servicing Criteria relating to Residential
             Funding Company, LLC.
34.2         Attestation Report of PricewaterhouseCoopers LLP on Assessment
             of Compliance with Servicing Criteria relating to GMAC Mortgage,
             LLC and Homecomings Financial, LLC (filed as Exhibit 33.2
             hereto).
34.3         Attestation Report of PricewaterhouseCoopers LLP on Assessment
             of Compliance with Servicing Criteria relating to Homecomings
             Financial, LLC (filed as Exhibit 33.3 hereto).


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34.4         Attestation Report of Ernst & Young LLP on Assessment of
             Compliance with Servicing Criteria relating to U.S. Bank
             National Association.
34.5         Attestation Report of KPMG LLP on Assessment of Compliance with
             Servicing Criteria relating to Wells Fargo Bank, National
             Association.
35.1         Servicer Compliance Statement of Residential Funding Company,
             LLC.
35.2         Servicer Compliance Statement of GMAC Mortgage, LLC.
35.3         Servicer Compliance Statement of Homecomings Financial, LLC.


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