SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


                                    FORM 10-K/A

[X]      Annual  report  pursuant  to  Section  13 or  15(d)  of the Securities
         Exchange   Act  of  1934   for the from August 1, 2001 (Commencement
         of Operations) to December 31, 2001.

[ ]     Transition report pursuant to Section 13 or 15(d) of the
         Securities Exchange Act of 1934 for the transition period from   to


                        Commission File Number 333-61840-13

              CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP.
             (Exact name of registrant as specified in its charter)

         Delaware                                          13-3320910
(State or other jurisdiction of                           I.R.S. Employer
incorporation or organization)                            Identification No.)

11 Madison Ave.
New York, New York                                             10010
(Address of Principal Executive Offices)                      (Zip Code)

       Registrant's telephone number, including area code :(212)538-3000

          CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP.
        CSFB MORTGAGE PASS-THROUGH CERTIFICATES SERIES 2001-S18
       (Title of each class of securities covered by this Form)

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 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. Yes [X] No [ ]

     Indicate by check mark if disclosure of delinquent  filers pursuant to Item
405 of Regulation S-K 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 this Form 10-K/A or any  amendment to
this Form 10-K/A. [X]

Documents incorporated by reference:  None



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AMENDMENT 1 OF 1

CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP.
CSFB MORTGAGE PASS-THROUGH CERTIFICATES SERIES 2001-S18
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PART IV

Item 14. Exhibits, Financial Statement Schedules and Reports on Form 8-K

(a) The following documents are filed as part of this report:

    (1) Financial Statements:
         Omitted.

    (2)  Financial Statement Schedules:
         Omitted.

    (3)  Exhibits:

   Annual  Servicer  Statement of  Compliance,  filed as Exhibit 99.1 hereto.
   Annual Statement of  Independent  Accountants  Report for the Servicer,
           filed as Exhibit 99.2 hereto.

(b)   Reports on Form 8-K: The  following  Current  Reports on Form 8-K were
      filed by the Registrant during the last quarter of 2001.

     Current  Reports   on Form 8-K,   dated   October 25,  2001,  November 26,
     2001,  and  December  26,  2001,  were filed for the  purpose of filing the
     Monthly  Statement  sent to the  Holders of the  Offered  Certificates  for
     payments made on the same dates.  The items reported in such Current Report
     were Item 5 (Other Events).


(c)   Exhibits to this report are listed in Item (14)(a)(3) above.

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SIGNATURE

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.


                                    JPMORGAN CHASE BANK,
                                    not in its individual capacity but solely
                                    as Trustee under the Agreement referred to
                                    herein


Date:  August 21, 2002              /s/ Thomas M. Britt
                                    -----------------------------------
                                    Thomas M. Britt
                                    Trust Officer



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                                 EXHIBIT INDEX

Exhibit     Description

 99.1       Servicer's Annual Statement of Compliance
 99.2       Servicer's Annual Independent Accountant's Report



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EXHIBIT 99.1 - Servicer's Annual Statement of Compliance


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Wilshire Financial Services Group Inc.
1776 SW Madison Street
Portland, Oregon  97205

Tel:    503.223.5600
Fax:    503.952.7476
www.wfsg.com


MANAGEMENT'S ASSERTION ON MINIMUM SERVICING STANDARDS

     As of and for the year ended December 31, 2001, Wilshire Credit Corporation
has complied in all material respects with the minimum  servicing  standards set
forth  in  the  Mortgage  Banker's   Association  of  America's  Uniform  Single
Attestation  Program  for  Mortgage  Bankers.  As of and for this  same  period,
Wilshire  Credit  Corporation  had in effect a  fidelity  bond in the  amount of
$10,000,000.00 and an errors and omission policy in the amount of $5,000,000.00.


/s/  Jay H. Memmott
Jay H. Memmott
President/CEO
March 22, 2002


/s/  Bruce A. Weinstein
Bruce A. Weinstein
Chief Financial Officer
March 22, 2002




Wilshire Credit Corporation
1776 SW Madison Street
Portland, Oregon  97205

Tel:    (503) 223-5600
        (800) 776-0100
Fax:    (503) 223-8799



ANNUAL SERVICING CERTIFICATION

In connection with those loans serviced by us we hereby certify that:

     1. All real estate taxes,  special  assessments  and any charges that might
become a lien upon the  property and which come due in the first  calendar  year
have been paid.

     2. All FHA insurance  premiums or private mortgage insurance  premiums,  if
applicable, have been paid and are in full force and effect.

     3. An extended mortgage impairment policy is in force,  adequately insuring
all loans in which Investor Savings has an interest.

     4. All interest and/or monthly payment  adjustments for ARM loans have been
made in accordance with the mortgage terms.

     5. Any exceptions to this  certification  are listed on an attachment along
with an explanation  concerning their  completion.  If there are none listed, it
will be considered that there are no exceptions.

     6. If applicable, all property inspections have been completed according to
the provisions of the servicing agreement.

     7. We have a complete Disaster Recovery Plan in place.



WILSHIRE CREDIT CORPORATION
By:  /s/  Jay Memmott
Title:  President

March 22, 2002

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OLYMPUS Servicing, LP
9600 Great Hills Trail, Suite #200W
Austin, TX  78759

Tel:  512.349.8300
Fax:  512.349.8371
www.OlympusServicing.com


OFFICER CERTIFICATE


     A review of the  activities of the Servicer  during the preceding  calendar
year and of its performance under servicing agreements, including this Servicing
Agreement has been made under such officer's supervision and to the best of such
officer's knowledge.

     Based on such review,  the  Servicer has compiled in all material  respects
with the minimum servicing standards set forth in the Uniform Single Attestation
Program for Mortgage  Bankers and has fulfilled all of its material  obligations
in all material respects throughout such year.

/s/  Jeff Neal
Jeff Neal
Chief Operating Officer



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EXHIBIT 99.2 - Servicer's Annual Independent Accountant's Report


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Deloitte & Touche LLP
Suite 3900
111 S.W. Fifth Avenue
Portland, Oregon 97204-3642

Tel: (503) 222-1341
Fax: (503) 324-2172


INDEPENDENT ACCOUNTANTS' REPORT

To Wilshire Credit Corporation:

     We have examined management's assertion about Wilshire Credit Corporation's
(the "Company"),  a  majority-owned  subsidiary of Wilshire  Financial  Services
Group Inc.,  compliance with the minimum servicing  standards  identified in the
Mortgage Bankers Association of America's Uniform Single Attestation Program for
Mortgage Bankers (USAP) as of and for the year ended December 31, 2001, included
in the  accompanying  management  assertion.  Management is responsible  for the
Company's compliance with those minimum servicing standards.  Our responsibility
is to express an opinion on management's assertion about the entity's compliance
based on our examination.

     Our examination  was made in accordance  with standards  established by the
American  Institute of Certified Public Accountants and,  accordingly,  included
examining,  on a test basis,  evidence about the Company's  compliance  with the
minimum  servicing   standards  and  performing  such  other  procedures  as  we
considered  necessary  in the  circumstances.  We believe  that our  examination
provides a reasonable basis for our opinion.  Our examination does not provide a
legal  determination  on the  Company's  compliance  with the minimum  servicing
standards.

     In our opinion,  management's  assertion that the Company complied with the
aforementioned minimum servicing standards as of and for the year ended December
31, 2001 is fairly stated, in all material respects.


/s/ Deloitte & Touche LLP
------------------------------

March 22, 2002


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KPMG
111 Congress Avenue, Suite 1100
Austin, TX  78701

Tel:  512.320.5200
Fax:  512.320.5100


INDEPENDENT ACCOUNTANTS' REPORT

General and Limited Partners
Olympus Servicing L.P.

     We have  examined  management's  assertion,  included  in the  accompanying
Management  Assertion,  that Olympus  Servicing  L.P.  complied with the minimum
servicing  standards set forth in the Mortgage Bankers  Association of America's
Uniform Single  Attestation  program for Mortgage Bankers as of and for the year
ended December 31, 2001.  Management is responsible for Olympus Servicing L.P.'s
compliance with those minimum  servicing  standards.  Our  responsibility  is to
express an opinion on management's assertion about the Partnership's  compliance
based on our examination.

     Our  examination  was  made  in  accordance  with  attestations   standards
established  by the  American  Institute of Certified  Public  Accountants  and,
accordingly,  included  examining,  on a  test  basis,  evidence  about  Olympus
Servicing L.P.'s compliance with the minimum servicing standards specified above
and  performing  such  other  procedures  as  we  considered  necessary  in  the
circumstances.  We believe that our examination  provides a reasonable basis for
our opinion.  Our examination does not provide a legal  determination on Olympus
Servicing L.P.'s compliance with the minimum servicing standards.

     In our opinion, management's assertion that Olympus Servicing L.P. complied
with the aforementioned minimum servicing standards as of and for the year ended
December 31, 2001 is fairly stated, in all material respects.

/s/  KPMG LLP

January 25, 2002


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