ASSIGNMENT AND ASSUMPTION AGREEMENT

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

        ASSIGNMENT AND ASSUMPTION  AGREEMENT,  dated September 28, 2006, between
Residential  Funding  Corporation,   a  StateDelaware  corporation  ("RFC")  and
Residential   Funding   Mortgage   Securities  I,  Inc.,  a   placeStateDelaware
corporation (the "Company").

                                    Recitals

        I. RFC has entered  into  contracts  ("Seller  Contracts")  with various
seller/servicers,  pursuant to which such  seller/servicers sell to RFC mortgage
loans.

        II. The Company  wishes to purchase from RFC certain  Mortgage Loans (as
hereinafter defined) sold to RFC pursuant to the Seller Contracts.

        III.  The  Company,  RFC,  as master  servicer  and U.S.  Bank  National
Association,  as trustee (the "Trustee"), are entering into a Series Supplement,
dated as of September 1, 2006 (the "Series  Supplement"),  to the Standard Terms
of Pooling and Servicing Agreement, dated as of September 1, 2006 (together with
the Series Supplement, the "Pooling and Servicing Agreement"), pursuant to which
the Company proposes to issue Mortgage Pass-Through Certificates, Series 2006-S9
(the  "Certificates")  consisting of classes  designated as the Class A-1, Class
A-2,  Class A-3,  Class A-4,  Class A-5,  Class A-6, Class A-7, Class A-8, Class
A-9,  Class A-10,  Class A-11,  Class A-12,  Class A-V, Class A-P, Class R-I and
Class R-II Certificates  (collectively,  the "Senior Certificates"),  Class M-1,
Class M-2 and Class M-3 Certificates (collectively,  the "Class M Certificates")
and Class B-1, Class B-2 and Class B-3 Certificates (collectively,  the "Class B
Certificates"),  representing  beneficial  ownership  interests  in a trust fund
consisting  primarily of a pool of mortgage  loans  identified in Exhibit One to
the Series Supplement (the "Mortgage Loans").

        IV. In connection with the purchase of the Mortgage  Loans,  the Company
will assign to RFC the Class A-P  Certificates,  Class A-V Certificates and a de
minimis  portion  of each of the  Class  R-I and Class  R-II  Certificates  (the
"Retained Certificates").

        V. In  connection  with  the  purchase  of the  Mortgage  Loans  and the
issuance of the  Certificates,  RFC wishes to make certain  representations  and
warranties  to the Company and to assign  certain of its rights under the Seller
Contracts  to the  Company,  and the Company  wishes to assume  certain of RFC's
obligations under the Seller Contracts.

        VI. The Company and RFC intend that the conveyance by RFC to the Company
of all its right,  title and interest in and to the Mortgage  Loans  pursuant to
this Agreement shall constitute a purchase and sale and not a loan.

        NOW THEREFORE,  in consideration of the recitals and the mutual promises
herein and other good and valuable consideration, the parties agree as follows:

Section 1. All  capitalized  terms used but not  defined  herein  shall have the
meanings assigned thereto in the Pooling and Servicing Agreement.

Section 2.  Concurrently  with the  execution  and delivery  hereof,  RFC hereby
assigns to the Company without recourse all of its right,  title and interest in
and to the  Mortgage  Loans,  including  all interest  and  principal,  and with
respect to the Sharia Mortgage Loans,  all amounts in respect of profit payments
and  acquisition  payments,  received on or with respect to the  Mortgage  Loans
after September 1, 2006 (other than payments of principal and interest, and with
respect to the Sharia Mortgage Loans,  all amounts in respect of profit payments
and  acquisition  payments,  due on the Mortgage  Loans in September  2006).  In
consideration  of such  assignment,  RFC or its  designee  will receive from the
Company in immediately  available funds an amount equal to $433,184,029.96  plus
the Class A-P Certificates,  the Class A-V Certificates and a de minimis portion
of the Retained  Certificates.  In connection  with such  assignment  and at the
Company's  direction,  RFC has in respect of each  Mortgage  Loan  endorsed  the
related  Mortgage Note (other than any Destroyed  Mortgage Note) to the order of
the Trustee and delivered an assignment of mortgage or security  instrument,  as
applicable,  in  recordable  form to the  Trustee  or its  agent.  A  "Destroyed
Mortgage Note" means a Mortgage Note the original of which was permanently  lost
or destroyed.

Section 3. RFC and the Company  agree that the sale of each  Pledged  Asset Loan
pursuant  to  this  Agreement  will  also  constitute  the   assignment,   sale,
setting-over,  transfer and  conveyance  to the Company,  without  recourse (but
subject to RFC's covenants, representations and warranties specifically provided
herein),  of all of RFC's obligations and all of RFC's right, title and interest
in, to and under,  whether now existing or  hereafter  acquired as owner of such
Pledged  Asset  Loan with  respect to any and all  money,  securities,  security
entitlements,  accounts, general intangibles, payment intangibles,  instruments,
documents, deposit accounts, certificates of deposit, commodities contracts, and
other  investment  property and other  property of whatever kind or  description
consisting  of,  arising  from or  related  to, (i) the  Credit  Support  Pledge
Agreement,  the Funding and Pledge Agreement among the Mortgagor or other Person
pledging the related Pledged Assets (the  "Customer"),  Combined  Collateral LLC
and National  Financial  Services  Corporation,  and the  Additional  Collateral
Agreement between GMAC Mortgage Corporation and the Customer (collectively,  the
"Assigned  Contracts"),  (ii) all rights, powers and remedies of RFC as owner of
such Pledged  Asset Loan under or in  connection  with the  Assigned  Contracts,
whether arising under the terms of such Assigned  Contracts,  by statute, at law
or in equity,  or otherwise arising out of any default by the Mortgagor under or
in connection with the Assigned Contracts,  including all rights to exercise any
election  or  option  or to make any  decision  or  determination  or to give or
receive any notice,  consent,  approval or waiver thereunder,  (iii) the Pledged
Amounts and all money,  securities,  security  entitlements,  accounts,  general
intangibles,  payment  intangibles,  instruments,  documents,  deposit accounts,
certificates of deposit,  commodities  contracts,  and other investment property
and other  property of whatever kind or  description  and, all cash and non-cash
proceeds of the sale,  exchange,  or redemption  of, and all stock or conversion
rights,  rights  to  subscribe,  liquidation  dividends  or  preferences,  stock
dividends,  rights to interest,  dividends,  earnings,  income,  rents,  issues,
profits, interest payments or other distributions of cash or other property that
secures a Pledged Asset Loan, (iv) all documents,  books and records  concerning
the foregoing  (including all computer programs,  tapes, disks and related items
containing  any such  information)  and (v) all  insurance  proceeds  (including
proceeds  from the  Federal  Deposit  Insurance  Corporation  or the  Securities
Investor  Protection  Corporation or any other insurance  company) of any of the
foregoing  or  replacements  thereof  or  substitutions  therefor,  proceeds  of
proceeds and the  conversion,  voluntary  or  involuntary,  of any thereof.  The
foregoing transfer,  sale,  assignment and conveyance does not constitute and is
not intended to result in the creation,  or an assumption by the Company, of any
obligation of RFC, or any other Person in connection  with the Pledged Assets or
under any agreement or instrument relating thereto,  including any obligation to
the Mortgagor, other than as owner of the Pledged Asset Loan.

        The Company and RFC intend that the  conveyance by RFC to the Company of
all its right,  title and interest in and to the Mortgage Loans pursuant to this
Section 2 shall be, and be construed as, a sale of the Mortgage  Loans by RFC to
the Company. It is, further, not intended that such conveyance be deemed to be a
pledge of the  Mortgage  Loans by RFC to the  Company  to secure a debt or other
obligation of RFC. However,  in the event that the Mortgage Loans are held to be
property of RFC, or if for any reason this Agreement is held or deemed to create
a security  interest in the Mortgage  Loans,  then it is intended  that (a) this
Agreement shall be a security  agreement  within the meaning of Articles 8 and 9
of the Minnesota Uniform  Commercial Code and the Uniform Commercial Code of any
other applicable  jurisdiction;  (b) the conveyance provided for in this Section
shall be  deemed  to be,  and  hereby  is, a grant  by RFC to the  Company  of a
security interest in all of RFC's right,  title and interest,  whether now owned
or  hereafter  acquired,  in and to any and  all  general  intangibles,  payment
intangibles,  accounts,  chattel paper, instruments,  documents,  money, deposit
accounts,  certificates of deposit,  goods, letters of credit, advices of credit
and  investment  property  consisting of, arising from or relating to any of the
following:   (A)  the  Mortgage  Loans,  including  (i)  with  respect  to  each
Cooperative Loan, the related Mortgage Note, Security  Agreement,  Assignment of
Proprietary  Lease,  Cooperative  Stock  Certificate,   Cooperative  Lease,  any
insurance  policies and all other  documents in the related  Mortgage  File (ii)
with respect to each Sharia  Mortgage  Loan,  the related  Sharia  Mortgage Loan
Security Instrument, Sharia Mortgage Loan Co-Ownership Agreement,  Obligation to
Pay, Assignment  Agreement and Amendment of Security  Instrument,  any insurance
policies  and all other  documents in the related  Mortgage  File and (iii) with
respect to each Mortgage Loan other than a Cooperative  Loan or Sharia  Mortgage
Loan, the related  Mortgage Note, the Mortgage,  any insurance  policies and all
other  documents in the related  Mortgage  File, (B) all monies due or to become
due pursuant to the Mortgage Loans in accordance  with the terms thereof and (C)
all proceeds of the conversion,  voluntary or involuntary, of the foregoing into
cash,  instruments,  securities or other property,  including without limitation
all amounts from time to time held or invested in the Certificate Account or the
Custodial Account, whether in the form of cash, instruments, securities or other
property; (c) the possession by the Trustee, the Custodian or any other agent of
the  Trustee of Mortgage  Notes or such other  items of  property as  constitute
instruments,  money, payment intangibles,  negotiable documents,  goods, deposit
accounts,  letters of credit,  advices of credit investment  property or chattel
paper shall be deemed to be possession by the secured party,  or possession by a
purchaser  or a  person  designated  by such  secured  party,  for  purposes  of
perfecting the security interest  pursuant to the Minnesota  Uniform  Commercial
Code  and the  Uniform  Commercial  Code of any  other  applicable  jurisdiction
(including,  without limitation,  Sections 8-106, 9-313 and 9-106 thereof);  and
(d)  notifications  to  persons  holding  such  property,  and  acknowledgments,
receipts or  confirmations  from persons holding such property,  shall be deemed
notifications to, or acknowledgments  receipts or confirmations from, securities
intermediaries, bailees or agents of, or persons holding for (as applicable) the
Trustee for the purpose of perfecting  such security  interest under  applicable
law.  RFC  shall,  to the  extent  consistent  with  this  Agreement,  take such
reasonable  actions as may be necessary to ensure that, if this  Agreement  were
determined  to create a security  interest in the  Mortgage  Loans and the other
property  described  above,  such security  interest would be determined to be a
perfected  security  interest of first priority under applicable law and will be
maintained as such throughout the term of this Agreement.  Without  limiting the
generality  of the  foregoing,  RFC shall prepare and deliver to the Company not
less than 15 days prior to any filing date, and the Company shall file, or shall
cause to be filed, at the expense of RFC, all filings  necessary to maintain the
effectiveness  of any original  filings  necessary under the Uniform  Commercial
Code as in effect in any jurisdiction to perfect the Company's security interest
in or lien on the Mortgage Loans,  including without limitation (x) continuation
statements, and (y) such other statements as may be occasioned by (1) any change
of name of RFC or the  Company,  (2) any  change  of  location  of the  place of
business  or the chief  executive  office  of RFC or,  (3) any  transfer  of any
interest of RFC in any Mortgage Loan.

        Notwithstanding the foregoing,  (i) the Master Servicer shall retain all
servicing rights (including,  without  limitation,  primary servicing and master
servicing)  relating to or arising out of the Mortgage Loans,  and all rights to
receive servicing fees, servicing income and other payments made as compensation
for such  servicing  granted to it under the  Pooling  and  Servicing  Agreement
pursuant  to the  terms and  conditions  set forth  therein  (collectively,  the
"Servicing  Rights")  and (ii) the  Servicing  Rights  are not  included  in the
collateral in which RFC grants a security  interest  pursuant to the immediately
preceding paragraph.

Section 4.  Concurrently  with the  execution and delivery  hereof,  the Company
hereby assigns to RFC without  recourse all of its right,  title and interest in
and to the Class A-P and Class A-V  Certificates and a de minimis portion of the
Retained Certificates as part of the consideration payable to RFC by the Company
pursuant to this Agreement.

Section  5. RFC  represents  and  warrants  to the  Company  that on the date of
execution  hereof  (or,  if  otherwise  specified  below,  as  of  the  date  so
specified):

(i) The  information  set forth in  Exhibit  One to the Series  Supplement  with
respect to each Mortgage Loan or the Mortgage Loans, as the case may be, is true
and correct,  in all material  respects,  at the date or dates  respecting which
such information is furnished;

(ii) Each mortgage loan with a  Loan-to-Value  Ratio at origination in excess of
80%,  will be  insured  by a  primary  mortgage  insurance  policy  (a  "Primary
Insurance  Policy")  covering  at  least  30% of the  principal  balance  of the
Mortgage Loan at  origination if the  Loan-to-Value  Ratio is between 95.00% and
90.01%,  at least 25% of the balance of the mortgage loan at  origination if the
Loan-to-Value  Ratio is  between  90.00%  and  85.01%,  and at least  12% of the
balance  of the  mortgage  loan at  origination  if the  Loan-to-Value  Ratio is
between  85.00% and 80.01%.  To the best of the Company's  knowledge,  each such
Primary Insurance Policy is in full force and effect and the Trustee is entitled
to the benefits thereunder;

(iii) Each Primary Insurance Policy insures the named insured and its successors
and  assigns,  and the issuer of the Primary  Insurance  Policy is an  insurance
company  whose  claims-paying  ability  is  currently  acceptable  to the Rating
Agencies;

(iv)  Immediately  prior to the assignment of the Mortgage Loans to the Company,
RFC had good title to, and was the sole owner of,  each  Mortgage  Loan free and
clear of any pledge,  lien,  encumbrance or security interest (other than rights
to servicing  and related  compensation  and,  with respect to certain  Mortgage
Loans,  the  monthly  payment  due on the first Due Date  following  the Cut-off
Date),  and no action  has been  taken or  failed to be taken by RFC that  would
materially  adversely  affect the  enforceability  of any  Mortgage  Loan or the
interests therein of any holder of the Certificates;

(v) No Mortgage Loan was 30 or more days  delinquent in payment of principal and
interest as of the Cut-off Date and no Mortgage Loan has been so delinquent more
than once in the 12-month period prior to the Cut-off Date;

(vi) Subject to clause (v) above as respects delinquencies, there is no default,
breach,  violation or event of acceleration  existing under any Mortgage Note or
Mortgage and no event  which,  with notice and  expiration  of any grace or cure
period, would constitute a default,  breach, violation or event of acceleration,
and no such default,  breach, violation or event of acceleration has been waived
by the Seller or by any other  entity  involved in  originating  or  servicing a
Mortgage Loan;

(vii) There is no  delinquent  tax or  assessment  lien  against  any  Mortgaged
Property;

(viii) No Mortgagor has any right of offset,  defense or  counterclaim as to the
related  Mortgage  Note  or  Mortgage  except  as  may  be  provided  under  the
Servicemembers Civil Relief Act;

(ix) None of the Mortgage Loans are Buy-Down Mortgage Loans;

(x)  There  are no  mechanics'  liens or  claims  for  work,  labor or  material
affecting any Mortgaged  Property