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                                                                   Exhibit 10.21

                                    TERM NOTE

$25,515,000.00                                            Long Beach, California
                                                                  March 21, 2000

      FOR VALUE RECEIVED, the undersigned INFONET SERVICES CORPORATION
("Borrower") promises to pay to the order of WELLS FARGO BANK, NATIONAL
ASSOCIATION ("Bank") at its office at its South Bay Regional Commercial Banking
Office at 111 West Ocean Boulevard, Suite 300, Long Beach, California 90802, or
at such other place as the holder hereof may designate, in lawful money of the
United States of America and in immediately available funds, the principal sum
of Twenty-five Million Five Hundred Fifteen Thousand Dollars ($25,515,000.00),
with interest thereon as set forth herein.

DEFINITIONS:

      As used herein, the following terms shall have the meanings set forth
after each, and any other term defined in this Note shall have the meaning set
forth at the place defined:

      (a) "Business Day" means any day except a Saturday, Sunday or any other
day on which commercial banks in California are authorized or required by law to
close.

      (b) "Fixed Rate Term" means a period commencing on a Business Day and
continuing for one (1), two (2), three (3) or six (6) months, as designated by
Borrower, during which all or a portion of the outstanding principal balance of
this Note bears interest determined in relation to LIBOR; provided however, that
no Fixed Rate Term may be selected for a principal amount less than One Million
Dollars ($1,000,000.00); and provided further, that no Fixed Rate Term shall
extend beyond the scheduled maturity date hereof. If any Fixed Rate Term would
end on a day which is not a Business Day, then such Fixed Rate Term shall be
extended to the next succeeding Business Day.

      (c) "LIBOR" means the rate per annum (rounded upward, if necessary, to the
nearest whole 1/8 of 1%) and determined pursuant to the following formula:

                LIBOR =           Base LIBOR
                        -------------------------------
                        100% - LIBOR Reserve Percentage

      (i) "Base LIBOR" means the rate per annum for United States dollar
deposits quoted by Bank as the Inter-Bank Market Offered Rate, with the
understanding that such rate is quoted by Bank for the purpose of calculating
effective rates of interest for loans making reference thereto, on the first day
of a Fixed Rate Term for delivery of funds on said date for a period of time
approximately equal to the number of days in such Fixed Rate Term and in an
amount approximately equal to the principal amount to which such Fixed Rate Term
applies. Borrower understands and agrees that Bank may base its quotation of the
Inter-Bank Market Offered Rate upon such offers or other market indicators of
the Inter-Bank Market as Bank in its discretion deems appropriate including, but
not limited to, the rate offered for U.S. dollar deposits on the London
Inter-Bank Market.

      (ii) "LIBOR Reserve Percentage" means the reserve percentage prescribed by
the Board of Governors of the Federal Reserve System (or any successor) for
"Eurocurrency


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      Liabilities" (as defined in Regulation D of the Federal Reserve Board, as
amended), adjusted by Bank for expected changes in such reserve percentage
during the applicable Fixed Rate Term.

      (d) "Prime Rate" means at any time the rate of interest most recently
announced within Bank at its principal office as its Prime Rate, with the
understanding that the Prime Rate is one of Bank's base rates and serves as the
basis upon which effective rates of interest are calculated for those loans
making reference thereto, and is evidenced by the recording thereof after its
announcement in such internal publication or publications as Bank may designate.

INTEREST:

      (a) Interest. The outstanding principal balance of this Note shall bear
interest (computed on the basis of a 360-day year, actual days elapsed) either
(i) at a fluctuating rate per annum one-half percent (0.5%) below the Prime Rate
in effect from time to time, or (ii) at a fixed rate per annum determined by
Bank to be one and three-quarters percent (1.75%) above LIBOR in effect on the
first day of the applicable Fixed Rate Term. When interest is determined in
relation to the Prime Rate, each change in the rate of interest hereunder shall
become effective on the date each Prime Rate change is announced within Bank.
With respect to each LIBOR selection hereunder, Bank is hereby authorized to
note the date, principal amount, interest rate and Fixed Rate Term applicable
thereto and any payments made thereon on Bank's books and records (either
manually or by electronic entry) and/or on any schedule attached to this Note,
which notations shall be prima facie evidence of the accuracy of the information
noted.

      (b) Selection of Interest Rate Options. At any time any portion of this
Note bears interest determined in relation to LIBOR, it may be continued by
Borrower at the end the Fixed Rate Term applicable thereto so that all or a
portion thereof bears interest determined in relation to the Prime Rate or to
LIBOR for a new Fixed Rate Term designated by Borrower. At any time any portion
of this Note bears interest determined in relation to the Prime Rate, Borrower
may convert all or a portion thereof so that it bears interest determined in
relation to LIBOR for a Fixed Rate Term designated by Borrower. At the time this
Note is disbursed or Borrower wishes to select a LIBOR option for all or a
portion of the outstanding principal balance hereof, and at the end of each
Fixed Rate Term, Borrower shall give Bank notice specifying: (i) the interest
rate option selected by Borrower; (ii) the principal amount subject thereto; and
(iii) for each LIBOR selection, the length of the applicable Fixed Rate Term.
Any such notice may be given by telephone so long as, with respect to each LIBOR
selection, (A) Bank receives written confirmation from Borrower not later than
three (3) Business Days after such telephone notice is given, and (B) such
notice is given to Bank prior to 10:00 a.m., California time, on the first day
of the Fixed Rate Term. For each LIBOR option requested hereunder, Bank will
quote the applicable fixed rate to Borrower at approximately 10:00 a.m.,
California time, on the first day of the Fixed Rate Term. If Borrower does not
immediately accept the rate quoted by Bank, any subsequent acceptance by
Borrower shall be subject to a redetermination by Bank of the applicable fixed
rate; provided however, that if Borrower fails to accept any such rate by 11:00
a.m., California time, on the Business Day such quotation is given, then the
quoted rate shall expire and Bank shall have no obligation to permit a LIBOR
option to be selected on such day. If no specific designation of interest is
made at the time this Note is disbursed or at the end of any Fixed Rate Term,
Borrower shall be deemed to have made a Prime Rate Interest selection for this
Note or the principal amount to which such Fixed Rate Term applied.


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      (c) Additional LIBOR Provisions.

      (i) If Bank at any time shall determine that for any reason adequate and
reasonable means do not exist for ascertaining LIBOR, then Bank shall promptly
give notice thereof to Borrower. If such notice is given and until such notice
has been withdrawn by Bank. then (A) no new LIBOR option may be selected by
Borrower, and (B) any portion of the outstanding principal balance hereof which
bears interest determined in relation to LIBOR, subsequent to the end of the
Fixed Rate Term applicable thereto, shall bear interest determined in relation
to the Prime Rate.

      (ii) If any law, treaty, rule, regulation or determination of a court or
governmental authority or any change therein or in the interpretation or
application thereof (each, a "Change in Law") shall make it unlawful for Bank
(A) to make LIBOR options available hereunder, or (B) to maintain interest rates
based on LIBOR, then in the former event, any obligation of Bank to make
available such unlawful LIBOR options shall immediately be cancelled, and in the
latter event, any such unlawful LIBOR-based interest rates then outstanding
shall be converted, at Bank's option, so that interest on the portion of the
outstanding principal balance subject thereto is determined in relation to the
Prime Rate; provided however, that if any such Change in Law shall permit any
LIBOR-based interest rates to remain in effect until the expiration of the Fixed
Rate Term applicable thereto, then such permitted LIBOR-based interest rates
shall continue in effect until the expiration of such Fixed Rate Term. Upon the
occurrence of any of the foregoing events, Borrower shall pay to Bank
immediately upon demand such amounts as may be necessary to compensate Bank for
any fines, fees, charges, penalties or other costs incurred or payable by Bank
as a result thereof and which are attributable to any LIBOR options made
available to Borrower hereunder, and any reasonable allocation made by Bank
among its operations shall be conclusive and binding upon Borrower.

      (iii) If any Change in Law or compliance by Bank with any request or
directive (whether or not having the force of law) from any central bank or
other governmental authority shall:

      (A)   subject Bank to any tax, duty or other charge with respect to any
            LIBOR options, or change the basis of taxation of payments to Bank
            of principal, interest, fees or any other amount payable hereunder
            (except for changes in the rate of tax on the overall net income of
            Bank); or

      (B)   impose, modify or hold applicable any reserve, special deposit,
            compulsory loan or similar requirement against assets held by,
            deposits or other liabilities in or for the account of, advances or
            loans by, or any other acquisition of funds by any office of Bank;
            or

      (C)   impose on Bank any other condition;

and the result of any of the foregoing is to increase the cost to Bank of
making, renewing or maintaining any LIBOR options hereunder and/or to reduce any
amount receivable by Bank in connection therewith, then in any such case,
Borrower shall pay to Bank immediately upon demand such amounts as may be
necessary to compensate Bank for any additional costs incurred by Bank and/or
reductions in amounts received by Bank which are attributable to such LIBOR
options. In determining which costs incurred by Bank and/or reductions in
amounts received by Bank are attributable to any LIBOR options made available to
Borrower hereunder,


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any reasonable allocation made by Bank among its operations shall be conclusive
and binding upon Borrower.

      (d) Payment of Interest. Interest accrued on this Note shall be payable on
the first day of each month, commencing April 1, 2000.

      (e) Default Interest. From and after the maturity date of this Note, or
such earlier date as all principal owing hereunder becomes due and payable by
acceleration or otherwise, the outstanding principal balance of this Note shall
bear interest until paid in full at an increased rate per annum (computed on the
basis of a 360-day year, actual days elapsed) equal to two percent (2%) above
the rate of interest from time to time applicable to this Note.

REPAYMENT AND PREPAYMENT:

      (a) Repayment. Principal shall be payable on the first day of each month
in installments of One Hundred Forty-one Thousand Seven Hundred Fifty Dollars
($141,750.00) each, commencing May 1, 2000, and continuing up to and including
March 1, 2015, with a final installment consisting of all remaining unpaid
principal due and payable in full on April 1, 2015.

      (b) Application of Payments. Each payment made on this Note shall be
credited first, to any interest then due and second, to the outstanding
principal balance hereof. All payments credited to principal shall be applied
first, to the outstanding principal balance of this Note which bears interest
determined in relation to the Prime Rate, if any, and second, to the outstanding
principal balance of this Note which bears interest determined in relation to
LIBOR, with such payments applied to the oldest Fixed Rate Term first.

      (c) Prepayment.

      Prime Rate. Borrower may prepay principal on any portion of this Note
which bears interest determined in relation to the Prime Rate at any time, in
any amount and without penalty.

      LIBOR. Borrower may prepay principal on any portion of this Note which
bears interest determined in relation to LIBOR at any time and in the minimum
amount of One Hundred Thousand Dollars ($100,000.00); provided however, that If
the outstanding principal balance of such portion of this Note is less than said
amount, the minimum prepayment amount shall be the entire outstanding principal
balance thereof. In consideration of Bank providing this prepayment option to
Borrower, or if any such portion of this Note shall become due and payable at
any time prior to the last day of the Fixed Rate Term applicable thereto by
acceleration or otherwise, Borrower shall pay to Bank immediately upon demand a
fee which is the sum of the discounted monthly differences for each month from
the month of prepayment through the month in which such Fixed Rate Term matures,
calculated as follows for each such month:

      (i)   Determine the amount of interest which would have accrued each month
            on the amount prepaid at the interest rate applicable to such amount
            had it remained outstanding until the last day of the Fixed Rate
            Term applicable thereto.

      (ii)  Subtract from the amount determined in (i) above the amount of
            interest which would have accrued for the same month on the amount
            prepaid for the remaining term of such Fixed Rate Term at LIBOR in
            effect on the date of prepayment for


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            new loans made for such term and in a principal amount equal to the
            amount prepaid.

      (iii) If the result obtained in (ii) for any month is greater than zero,
            discount that difference by LIBOR used in (ii) above.

Borrower acknowledges that prepayment of such amount may result in Bank
incurring additional costs, expenses and/or liabilities, and that it is
difficult to ascertain the full extent of such costs, expenses and/or
liabilities. Borrower, therefore, agrees to pay the above-described prepayment
fee and agrees that said amount represents a reasonable estimate of the
prepayment costs, expenses and/or liabilities of Bank. If Borrower fail to pay
any prepayment fee when due, the amount of such prepayment fee shall thereafter
bear interest until paid at a rate per annum two percent (2.0%) above the Prime
Rate in effect from time to time (computed on the basis of a 360-day year,
actual days elapsed).

      All prepayments of principal shall be applied on the most remote principal
installment or installments then unpaid.

EVENTS OF DEFAULT:

      The occurrence of any of the following shall constitute an "Event of
Default" under this Note:

      (a) The failure to pay any principal, interest, fees or other charges when
due hereunder or under any contract, instrument or document executed in
connection with this Note.

      (b) The filing of a petition by or against Borrower under any provisions
of the Bankruptcy Reform Act, Title 11 of the United States Code, as amended or
recodified from time to time, or under any similar or other law relating to
bankruptcy, insolvency, reorganization or other relief for debtors; the
appointment of a receiver, trustee, custodian or liquidator of or for any part
of the assets or property of Borrower; Borrower becomes insolvent, makes a
general assignment for the benefit of creditors or is generally not paying its
debts as they become due; or any attachment or like levy on any property of
Borrower.

      (c) The dissolution or liquidation of Borrower.

      (d) Any default in the payment or performance of any obligation, or any
defined event of default, under any provisions of any contract, instrument or
document pursuant to which Borrower has incurred any obligation for borrowed
money, any purchase obligation, or any other liability of any kind to any person
or entity, including the holder, including without limitation any default or
defined event of default under the Syndicated Credit Agreement (as defined in
the addendum attached hereto and made a part hereof); provided, however, that in
the case of a default or defined event of default under the terms of
indebtedness to a person or entity other than the holder, and other than under
the Syndicated Credit Agreement, such indebtedness is in excess of
$10,000,000.00 for all such defaults combined.

      (e) Any financial statement provided by Borrower to Bank proves to be
incorrect, false or misleading in any material respect.

      (f) Any sale or transfer of all or a substantial or material part of the
assets of Borrower other than in the ordinary course of its business, it being
understood and agreed that


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sales and transfers by Borrower of assets with a fair value of less than
twenty-five percent (25%) of Borrower's total assets in the aggregate for all
such sales and transfers combined shall not constitute an Event of Default
hereunder.

      (g) Any violation or breach of any provision of, or any defined event of
default under, any addendum to this Note or any loan agreement, guaranty,
security agreement, deed of trust, mortgage or other document executed in
connection with or securing this Note, and with respect to any such violation,
breach or defined event of default which by its nature can be cured, such
violation, breach or defined event of default shall continue for a period of
twenty (20) days from its occurrence.

MISCELLANEOUS:

      (a) Remedies. Upon the sale, transfer, hypothecation, assignment or other
encumbrance, whether voluntary, involuntary or by operation of law, of all or
any interest in any real property securing this Note (except as specifically
permitted in the deed of trust securing this Note), or upon the occurrence of
any Event of Default, the holder of this Note, at the holder's option, may
declare all sums of principal and interest outstanding hereunder to be
immediately due and payable without presentment, demand, notice of
nonperformance, notice of protest, protest or notice of dishonor, all of which
are expressly waived by Borrower. Borrower shall pay to the holder immediately
upon demand the full amount of all payments, advances, charges, costs and
expenses, including reasonable attorneys' fees (to include outside counsel fees
and all allocated costs of the holder's in-house counsel), expended or incurred
by the holder in connection with the enforcement of the holder's rights and/or
the collection of any amounts which become due to the holder under this Note,
and the prosecution or defense of any action in any way related to this Note,
including without limitation, any action for declaratory relief, whether
incurred at the trial or appellate level, in an arbitration proceeding or
otherwise, and including any of the foregoing incurred in connection with any
bankruptcy proceeding (including without limitation, any adversary proceeding,
contested matter or motion brought by Bank or any other person) relating to
Borrower or any other person or entity.

      (b) Obligations Joint and Several. Should more than one person or entity
sign this Note as a Borrower, the obligations of each such Borrower shall be
joint and several.

      (c) Governing Law. This Note shall be governed by and construed in
accordance with the laws of the State of California.

      IN WITNESS WHEREOF, the undersigned has executed this Note as of the date
first written above.


INFONET SERVICES CORPORATION

By:  /s/ Ernest U. Gambaro
    -----------------------------
Title: Secretary, General Counsel
       --------------------------


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<PAGE>

                           ADDENDUM TO PROMISSORY NOTE
                        (PRIME/LIBOR PRICING ADJUSTMENTS)

      THIS ADDENDUM is attached to and made a part of that certain promissory
note executed by INFONET SERVICES CORPORATION ("Borrower") and payable to WELLS
FARGO BANK, NATIONAL ASSOCIATION ("Bank"), or order, dated as of March 21, 2000,
in the principal amount of Twenty-five Million Five Hundred Fifteen Thousand
Dollars ($25,515,000.00) (the "Note").

      The following provisions are hereby incorporated into the Note:

      1. Borrower shall provide to Bank all of the following, in form and detail
satisfactory to Bank:

      (a) not later than 90 days after and as of the end of each fiscal year, an
audited consolidated financial statement of Borrower, prepared by a certified
public accountant acceptable to Bank, to include a balance sheet and an income
statement;

      (b) not later than 45 days after and as of the end of each fiscal quarter,
a consolidated financial statement of Borrower, prepared by Borrower, to include
a balance sheet and an income statement; and

      (c) a copy of the "Compliance Certificate" required to be delivered by
Borrower pursuant to the terms and conditions of that certain Credit Agreement
dated as of August 17, 1999 by and among Borrower, the various lenders named
therein, Merrill Lynch & Co., as lead arranger, book manager and syndication
agent, The Bank of Nova Scotia, as administrative agent, and Societe Generale,
as documentation agent (the "Syndicated Credit Agreement").

      (d) from time to time such financial and other information as Bank may
reasonably request.

      2. Borrower shall maintain a "Consolidated Leverage Ratio" and a
"Consolidated Interest Coverage Ratio" as defined in and as set forth in the
Syndicated Credit Agreement as in effect as of the date hereof. Any changes
which may be made to such covenants in the Syndicated Credit Agreement shall not
be effective hereunder unless consented to in writing by Bank.

      3. ARBITRATION:

      (a) Arbitration. Upon the demand of any party, any Dispute shall be
resolved by binding arbitration in accordance with the terms of this Note. A
"Dispute" shall mean any action, dispute, claim or controversy of any kind,
whether in contract or tort, statutory or common law, legal or equitable, now
existing or hereafter arising under or in connection with, or in any way
pertaining to, this Note and each other document, contract and instrument
required hereby or now or hereafter delivered to Bank in connection herewith
(collectively, the "Documents"), or any past, present or future extensions of
credit and other activities, transactions or obligations of any kind related
directly or indirectly to any of the Documents, including without limitation,
any of the foregoing arising in connection with the exercise of any self-help,
ancillary or other remedies pursuant to any of the Documents. Any party may by
summary proceedings bring an action in court to compel arbitration of a Dispute.
Any party who fails or refuses to submit to arbitration


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following a lawful demand by any other party shall bear all costs and expenses
incurred by such other party in compelling arbitration of any Dispute.

      (b) Governing Rules. Arbitration proceedings shall be administered by the
American Arbitration Association ("AAA") or such other administrator as the
parties shall mutually agree upon in accordance with the AAA Commercial
Arbitration Rules. All Disputes submitted to arbitration shall be resolved in
accordance with the Federal Arbitration Act (Title 9 of the United States Code),
notwithstanding any conflicting choice of law provision in any of the Documents.
The arbitration shall be conducted at a location in California selected by the
AAA or other administrator. If there is any inconsistency between the terms
hereof and any such rules, the terms and procedures set forth herein shall
control. All statutes of limitation applicable to any Dispute shall apply to any
arbitration proceeding. All discovery activities shall be expressly limited to
matters directly relevant to the Dispute being arbitrated. Judgment upon any
award rendered in an arbitration may be entered in any court having
jurisdiction; provided however, that nothing contained herein shall be deemed to
be a waiver by any party that is a bank of the protections afforded to it under
12 U.S.C. (S).91 or any similar applicable state law.

      (C) No Waiver; Provisional Remedies, SeIf-Help and Foreclosure. No
provision hereof shall limit the right of any party to exercise self-help
remedies such as setoff, foreclosure against or sale of any real or personal
property collateral or security, or to obtain provisional or ancillary remedies,
including without limitation injunctive relief, sequestration, attachment,
garnishment or the appointment of a receiver, from a court of competent
jurisdiction before, after or during the pendency of any arbitration or other
proceeding. The exercise of any such remedy shall not waive the right of any
party to compel arbitration or reference hereunder.

      (d) Arbitrator Qualifications and Powers; Awards. Arbitrators must be
active members of the California State Bar or retired judges of the state or
federal judiciary of California, with expertise in the substantive law
applicable to the subject matter of the Dispute. Arbitrators arm empowered to
resolve Disputes by summary rulings in response to motions filed prior to the
final arbitration hearing. Arbitrators (i) shall resolve all Disputes in
accordance with the substantive law of the state of California, (ii) may grant
any remedy or relief that a court of the state of California could order or
grant within the scope hereof and such ancillary relief as is necessary to make
effective any award, and (iii) shall have the power to award recovery of all
costs and fees, to impose sanctions and to take such other actions as they deem
necessary to the same extent a judge could pursuant to the Federal Rules of
Civil Procedure, the California Rules of Civil Procedure or other applicable
law. Any Dispute in which the amount in controversy is $5,000,000 or less shall
be decided by a single arbitrator who shall not render an award of greater than
$5,000,000 (including damages, costs, fees and expenses). By submission to a
single arbitrator, each party expressly waives any right or claim to recover
more than $5,000,000. Any Dispute in which the amount in controversy exceeds
5,000,000 shall be decided by majority vote of a panel of three arbitrators;
provided however, that all three arbitrators must actively participate in all
hearings and deliberations.

      (e) Real Property Collateral; Judicial Reference. Notwithstanding anything
herein to the contrary, no Dispute shall be submitted to arbitration if the
Dispute concerns indebtedness secured directly or indirectly, in whole or in
part, by any real property unless (i) the holder of the mortgage, lien or
security interest specifically elects in writing to proceed with the
arbitration, or (ii) all parties to the arbitration waive any rights or benefits
that might accrue to them by virtue of the single action rule statute of
California, thereby agreeing that all indebtedness and obligations of the
parties, and all mortgages, liens and security interests securing such
Indebtedness and obligations, shall remain fully valid and enforceable. If any
such Dispute is


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not submitted to arbitration, the Dispute shall be referred to a referee in
accordance with California Code of Civil Procedure Section 638 et seq., and this
general reference agreement is intended to be specifically enforceable in
accordance with said Section 638. A referee with the qualifications required
herein for arbitrators shall be selected pursuant to the AAA's selection
procedures. Judgment upon the decision rendered by a referee shall be entered in
the court in which such proceeding was commenced in accordance with California
Code of Civil Procedure Sections 644 end 645.

      (f) Miscellaneous. To the maximum extent practicable, the AAA, the
arbitrators and the parties shall take all action required to conclude any
arbitration proceeding within 180 days of the filing of the Dispute with the
AAA. No arbitrator or other party to an arbitration proceeding may disclose the
existence, content or results thereof, except for disclosures of information by
a party required in the ordinary course of its business, by applicable law or
regulation, or to the extent necessary to exercise any judicial review rights
set forth herein. If more than one agreement for arbitration by or between the
parties potentially applies to a Dispute, the arbitration provision most
directly related to the Documents or the subject matter of the Dispute shall
control. This Note may be amended or modified only in writing signed by Bank and
Borrower. If any provision of this Note shall be held to be prohibited by or
invalid under applicable law, such provision shall be ineffective only to the
extent of such prohibition or invalidity, without invalidating the remainder of
such provision or any remaining provisions of this Note. This arbitration
provision shall survive termination, amendment or expiration of any of the
Documents or any relationship between the parties.

      IN WITNESS WHEREOF, this Addendum has been executed as of the same date as
the Note.


INFONET SERVICES CORPORATION

By:  /s/ Ernest U. Gambaro
    -----------------------------
Title: Secretary, General Counsel
       --------------------------


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