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                                                                   Exhibit 10.16

                 NINTH AMENDMENT TO LOAN AND SECURITY AGREEMENT

      THIS NINTH AMENDMENT TO LOAN AND SECURITY AGREEMENT (this "Amendment") is
entered into as of the 11th day of March, 2005 by and among the banks that are
or may from time to time become parties hereto (individually a "Bank" and
collectively, the "Banks"), LASALLE BANK NATIONAL ASSOCIATION, a national
banking association (in its individual capacity, "LaSalle"), as agent ("Agent")
for the Banks, and SIGMATRON INTERNATIONAL, INC., a Delaware corporation (the
"Borrower").

                              W I T N E S S E T H:

      WHEREAS, Agent, the Banks and Borrower are parties to that certain Loan
and Security Agreement dated as of August 25, 1999, as amended by that certain
Amendment to Loan and Security Agreement dated as of August 31, 2000, that
certain Forbearance Agreement and Second Amendment to Loan and Security
Agreement dated as of February 1, 2001, that certain Forbearance Agreement and
Third Amendment to Loan and Security Agreement dated as of May 31, 2001, that
certain Forbearance Agreement and Fourth Amendment to Loan and Security
Agreement dated as of July 31, 2001, that certain Fifth Amendment to Loan and
Security Agreement dated as of November 30, 2001, that certain Sixth Amendment
to Loan and Security Agreement dated as of April 22, 2002, that certain Seventh
Amendment to Loan and Security Agreement dated as of October 16, 2002 and that
certain Eighth Amendment to Loan and Security Agreement dated as of February 19,
2004 (the Original Agreement and all of the foregoing amendments are
collectively referred to as the "Agreement"); and

      WHEREAS, the Borrower and the Banks have agreed to further amend the
Agreement to, among other items, (i) extend the maturity date of the Revolving
Credit Commitment (as defined in the Agreement), and (ii) modify certain
interest rate provisions and financial covenants, all in accordance with the
terms and conditions of this Amendment.

      NOW, THEREFORE, for and in consideration of the premises and mutual
agreements herein contained and for the purposes of setting forth the terms and
conditions of this Amendment, the parties, intending to be bound, hereby agree
as follows:

      1. Incorporation of the Agreement. All capitalized terms which are not
defined hereunder shall have the same meanings as set forth in the Agreement,
and the Agreement, to the extent not inconsistent with this Amendment, is
incorporated herein by this reference as though the same were set forth in its
entirety. To the extent any terms and provisions of the Agreement are
inconsistent with the amendments set forth in Paragraph 2 below, such terms and
provisions shall be deemed superseded hereby. Except as specifically set forth
herein, the Agreement shall remain in full force and effect and its provisions
shall be binding on the parties hereto.

      2. Amendment of the Agreement.

            (a) The definition of the terms "Letter of Credit Limit", "Maturity
Date" and "Revolving Note" appearing in Paragraph 1.1 of the Agreement are
hereby amended and restated to read as follows:

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            "Letter of Credit Limit" means Four Million Dollars ($4,000,000).

            "Maturity Date" means September 30, 2006 with respect to all Loans.

            "Revolving Note" means those certain Substitute Revolving Notes
      dated as of March 11, 2005 payable by Borrower to each of LaSalle Bank
      National Association and Charter One Bank in the maximum principal amounts
      of $7,800,000 and $5,200,000, respectively, as each may be amended,
      modified, substituted or restated from time to time, together with all
      renewals and exchanges therefore.

            (b) Paragraphs 11.2(f)(vi) and (v) of the Agreement are hereby
amended and restated to read as follows:

            (vi) Maintain EBITDA of not less than the following amounts during
      the periods set forth below measured quarterly on a rolling twelve month
      basis:

<TABLE>
<CAPTION>
             PERIOD                                              AMOUNT
             ------                                              ------
<S>                                                             <C>
January 31, 2005 - October 31, 2005                             $6,000,000

November 1, 2005 and at all times thereafter                    $5,000,000
</TABLE>

            (v) Not permit the aggregate amount of Capital Expenditures to
      exceed $6,000,000 in any fiscal year (excluding any Capital Expenditures
      associated with Borrower's plant located in China).

            (c) Schedule 1.1 to the Agreement is hereby amended and restated
with Schedule 1.1 attached hereto.

      3. Representations and Warranties. The representations and warranties set
forth in Paragraph 11.1 and all covenants set forth in Paragraphs 11.2 and 11.3
of the Agreement shall be deemed remade and affirmed as of the date hereof by
Borrower, except any and all references to the Agreement in such
representations, warranties and covenants shall be deemed to include this
Amendment.

      4. Delivery of Documents/Information. Prior to entering into this
Amendment, Agent shall have received from Borrower the following fully executed
documents, in form and substance satisfactory to Agent and each Bank, and all of
the transactions contemplated by each such document shall have been consummated
or each condition contemplated by each such document shall have been satisfied:

            (a)   this Amendment;

            (b)   Substitute Revolving Note of each Bank;

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            (c)   Secretary's Certificate of Borrower with resolutions and
                  incumbency;

            (d)   Officer's Certificate (Closing Bring-Down) of Borrower; and

            (e)   such other documents, certificates and opinions as Agent may
                  request.

      5. Reference to the Effect on the Agreement.

            (a) References. Upon the date of this Amendment and on and after the
date hereof, each reference in the Agreement to "this Agreement," "hereunder,"
"hereof," "herein" or words of like import shall mean and be a reference to the
Agreement, as amended hereby.

            (b) Ratification. As specifically modified above, the Agreement and
all other documents, instruments and agreements executed and/or delivered in
connection therewith shall remain in full force and effect, and are hereby
ratified and confirmed.

      6. Representations and Warranties of the Borrower. Borrower hereby
represents and warrants to Agent and the Banks as of the date hereof as follows:

            (a) The execution and delivery of this Amendment and the performance
by Borrower of its obligations hereunder are within the Borrower's powers and
authority, have been duly authorized by all necessary corporate action and do
not and will not contravene or conflict with the Articles of Incorporation or
By-laws of Borrower.

            (b) The Agreement (as amended by this Amendment) and the Other
Agreements constitute legal, valid and binding obligations enforceable in
accordance with their terms by Agent and the Banks against Borrower, and
Borrower expressly reaffirms each of its obligations under the Agreement (as
amended by this Amendment) and each of the Other Agreements, including, without
limitation, the Borrower's Liabilities. Borrower further expressly acknowledges
and agrees that Agent has a valid, duly perfected, first priority and fully
enforceable security interest in and lien against each item of Collateral except
as otherwise set forth in the Agreement. Borrower agrees that it shall not
dispute the validity or enforceability of the Agreement (as it was stated before
and after this Amendment) or any of the Other Agreements or any of its
respective obligations thereunder, or the validity, priority, enforceability or
extent of Agent's security interest in or lien against any item of Collateral,
in any judicial, administrative or other proceeding;

            (c) No consent, order, qualification, validation, license, approval
or authorization of, or filing, recording, registration or declaration with, or
other action in respect of, any governmental body, authority, bureau or agency
or other Person is required in connection with the execution, delivery or
performance of, or the legality, validity, binding effect or enforceability of,
this Amendment; and

            (d) The execution, delivery and performance of this Amendment by
Borrower does not and will not violate any law, governmental regulation,
judgment, order or decree applicable to Borrower and does not and will not
violate the provisions of, or constitute a default or any event of default
under, or result in the creation of any security interest or lien upon any
property of Borrower pursuant to, any indenture, mortgage, instrument, contract,
agreement or

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other undertaking to which Borrower is a party or is subject or by which
Borrower or any of its real or personal property may be bound.

      7. Releases; Indemnities.

            (a) In further consideration of the Banks' execution of this
Amendment, Borrower, and on behalf of its successors, assigns, subsidiaries and
Affiliates, hereby forever release Agent and each Bank and their respective
successors, assigns, parents, subsidiaries, Affiliates, officers, employees
directors, agents and attorneys (collectively, the "Releasees") from any and all
debts, claims, demands, liabilities, responsibilities, disputes, causes,
damages, actions and causes of action (whether at law or in equity) and
obligations of every nature whatsoever, whether liquidated or unliquidated,
known or unknown, matured or unmatured, fixed or contingent (collectively,
"Claims"), that Borrower may have against the Releasees which arise from or
relate to any actions which the Releasees may have taken or omitted to take
prior to the date this Amendment was executed, including without limitation with
respect to Borrower's Liabilities, any Collateral, the Agreement, any Other
Agreement and any third parties liable in whole or in part for Borrower's
Liabilities. This provision shall survive and continue in full force and effect
whether or not Borrower shall satisfy all other provisions of this Amendment,
the Other Agreements or the Agreement, including payment in full of Borrower's
Liabilities.

            (b) Borrower hereby agrees that its obligation to indemnify and hold
the Releasees harmless as set forth in Paragraph 7(a) of this Amendment shall
include an obligation to indemnify and hold the Releasees harmless with respect
to any and all liabilities, obligations, losses, penalties, actions, judgments,
suits, costs, expenses or disbursements of any kind or nature whatsoever
incurred by the Releasees, or any of them, whether direct, indirect or
consequential, as a result of or arising from or relating to any proceeding by,
or on behalf of, any Person, including, without limitation, officers, directors,
agents, trustees, creditors, partners or shareholders of Borrower, whether
threatened or initiated, asserting any claim for legal or equitable remedy under
any statute, regulation or common law principle arising from or in connection
with the negotiation, preparation, execution, delivery, performance,
administration and enforcement of this Amendment or any other document executed
in connection herewith. The foregoing indemnity shall survive the payment in
full of the Borrower's Liabilities and the termination of this Amendment, the
Agreement and the Other Agreements.

      8. Fees and Expenses. The Borrower agrees to pay on demand all costs, fees
and expenses of or incurred by the Agent in connection with the evaluation,
negotiation, preparation, execution and delivery of this Amendment and the other
instruments and documents executed and delivered in connection with the
transactions described herein (including the filing or recording thereof),
including, but not limited to, the reasonable fees and expenses of counsel for
the Agent, search fees and taxes payable in connection with this Amendment and
any future amendments to the Agreement.

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      9. Counterparts. This Amendment may be executed in two or more
counterparts, each of which shall be deemed an original, and all of which
together shall constitute one and the same instrument.

                            [SIGNATURE PAGE FOLLOWS]

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         (NINTH AMENDMENT TO LOAN AND SECURITY AGREEMENT SIGNATURE PAGE)

      IN WITNESS WHEREOF, the parties hereto have duly executed this Ninth
Amendment to Loan and Security Agreement as of the date first above written.

                                          LASALLE BANK NATIONAL ASSOCIATION,
                                          for itself and as Agent

                                          By: /s/ Sara A. Huizinga
                                              -----------------------
                                          Its: Assistant Vice President

                                          CHARTER ONE BANK, N.A., as a Bank

                                          By:  /s/ Raullo M. Eanes
                                               -----------------------
                                          Its: Vice President

                                          SIGMATRON INTERNATIONAL, INC.

                                          By:  /s/ Linda K. Blake
                                                ----------------------
                                          Its: Chief Financial Officer

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