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                                                                    Exhibit 10.1




                        FORM OF EXCHANGE AGENT AGREEMENT

     This EXCHANGE AGENT AGREEMENT (this "Agreement") dated as of _ , 2000
between IMPSAT Fiber Networks, Inc., a Delaware corporation ("IMPSAT"), and The
Bank of New York, a banking corporation formed under the laws of the State of
New York, United States (the "Exchange Agent").

                              W I T N E S S E T H:

     WHEREAS, IMPSAT is offering to exchange (the "Exchange Offer") all of its
outstanding 13-3/4% Senior Notes due 2005 (the "Old Notes"), of which an
aggregate of $300,000,000 in principal amount are outstanding as of the date
hereof, for an equal principal amount of newly issued 13-3/4% Senior Notes due
2005 (the "New Notes"), on the terms and in the manner set forth in the
Prospectus, dated April [ ], 2000 (the "Exchange Offer Prospectus"); and

     WHEREAS, IMPSAT wishes to appoint the Exchange Agent as its agent for the
purpose of administering the Exchange Offer and the Exchange Agent wishes to
accept such appointment.

     NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein, the parties agree as follows:

     1.   Appointment of Exchange Agent; Performance of Duties.  IMPSAT hereby
appoints the Exchange Agent as its agent for the Exchange Offer, and the
Exchange Agent accepts such appointment subject to the terms and conditions
contained in this Agreement.

     2.   Documents.  The Exchange Agent shall establish an account with respect
to the Old Notes at the Depository Trust Company ("DTC") for purposes of the
Exchange Offer within two business days after the date of the Exchange Offer
Prospectus so that any Participant (as defined herein) may make book-entry
delivery of the Old Notes by causing DTC to transfer such Old Notes into such
account in accordance with DTC's procedures for such transfer.  IMPSAT shall
provide the Exchange Agent with copies of a letter of transmittal substantially
in  the form of Exhibit A attached hereto (the "Letter of Transmittal").  The
Exchange Agent shall request from DTC no later than the effective date of the
Exchange Offer a Special Security Position Listing of all participants eligible
to participate in the Exchange Offer (the "Participants") and the amount of Old
Notes beneficially owned by each such Participant; provided, however, that the
Exchange Agent shall not be responsible for any changes in the Participants or
of the beneficial ownership of the Old Notes during the Exchange Offer.  The
Exchange Agent shall make copies of the Letter of Transmittal available to
Holders (as such term is defined in the Letter of Transmittal) and the
Participants upon requests directed to The Bank of New York, Corporate Trust
Administration, 101 Barclay Street, Floor 21 West, New York, New York 10286 by
registered or certified mail or by overnight courier.


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     3.   Exchange Agent Responsibilities.  The Exchange Agent shall examine the
Letters of Transmittal (or a facsimile thereof) and other documents received by
it or ascertain that (a) each Letter of Transmittal is completed and duly
executed in accordance with the instructions therefor and (b) any other
document required by the instructions accompanying the Letters of Transmittal
is completed and duly executed in accordance with such instructions.  Except as
otherwise provided in this Paragraph 3, Old Notes shall not be deemed to be
properly tendered unless all of the foregoing requirements are met prior to the
Expiration Date (as defined in the Exchange Offer Prospectus).  The Exchange
Agent shall take all steps as it shall deem reasonable and appropriate to cause
the person tendering Old Notes pursuant to the Exchange Offer to correct any
defect that exists in any Letter of Transmittal or accompanying document.  In
the event that the Exchange Agent is unable to cause the correction of any such
defect, the Exchange Agent shall promptly send to IMPSAT any Letter of
Transmittal or other document or copies thereof containing any defect therein,
which in its judgment would prevent acceptance thereof, together with a request
for instructions as to actions to be taken with respect thereto in accordance
with Paragraph 8(f) of this Agreement.  All questions with respect to
compliance with the requirement of this Paragraph 3 will be determined by
IMPSAT, which determination shall be final and binding for the purposes of this
Agreement.  IMPSAT reserves the right, if it so elects in its discretion, to
waive the failure of any delivery of Old Notes, Letter of Transmittal or other
document pursuant to the Exchange Offer to comply with any requirement of  this
Paragraph 3 or of the Letter of Transmittal.  IMPSAT reserves the right to
terminate or, prior to the Expiration Date, amend the Exchange Offer as
provided in the Exchange Offer Prospectus.  If notified by IMPSAT of
termination of the Exchange Offer, the Exchange Agent shall promptly return all
tendered Old Notes to the tendering Holders.  If notified by IMPSAT of an
amendment of the Exchange Offer, the Exchange Agent shall follow the reasonable
instruction of IMPSAT contained in such notice to the extent consistent with
this Agreement.  Each day upon which the Exchange Agent receives one or more
Letters of Transmittal, the Exchange Agent shall provide IMPSAT with a written
account of the following information:  (1) the number of properly tendered Old
Notes submitted that day; (2) the cumulative number of properly tendered Old
Notes submitted and not properly withdrawn through such day; (3) the number of
Old Notes covered by defective tenders submitted that day; (4) the number of
Old Notes which are submitted that day pursuant to the guaranteed delivery
procedures contained in the Letter of Transmittal; and (5) the cumulative
number of Old Notes covered by uncorrected defective tenders as of such date.


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     4.   Acceptances and Exchange.

          (a)  At any time after the Expiration Date (as defined in the Exchange
Offer Prospectus), upon receiving a notice from IMPSAT directing the exchange
of properly tendered Old Notes, the Exchange Agent shall, as agent of IMPSAT
and subject to all the conditions of the Exchange Offer, accept for exchange
all Old Notes properly tendered in accordance with this Agreement that are not
properly withdrawn prior to the Expiration Date (as defined in the Exchange
Offer Prospectus).  Thereafter, unless notified otherwise by IMPSAT, the
Exchange Agent shall continue to accept for exchange all Old Notes that are
properly delivered to the Exchange Agent pursuant to Notices of Guaranteed
Delivery (as defined in the Exchange Offer Prospectus) but shall not accept any
other Old Notes for exchange.

          (b)  Following such acceptance of Old Notes, the Exchange Agent shall
promptly present all such Old Notes to the The Bank of New York, as Registrar
and Transfer Agent for the New Notes (in such capacity, the "Registrar"), with
instructions to cause such Old Notes to be marked as "canceled" in the name of
IMPSAT in the appropriate registers.  The Exchange Agent promptly shall notify
the Registrar of (A) the names of the Holders on whose behalf Old Notes have
been so presented and the number of Old Notes so presented on behalf of each
and (B) the instructions for delivery of New Notes provided in the Letters of
Transmittal submitted by each such Holder.  The Exchange Agent shall from time
to time request the Registrar to issue such New Notes as are required for
delivery hereunder.

     5.   Assignees; Signatures.  If a New Note or beneficial ownership thereof
is to be delivered to, or reflected on the records of DTC as belonging to, an
assignee of the Holder or beneficial owner of the surrendered Old Notes, the
assignee of the Holder or the beneficial owner shall pay to the Exchange Agent
the amount of any transfer taxes applicable to such transfer unless
satisfactory evidence of the payment of such tax, or exception therefrom, is
submitted.

     The signature (or signatures, in the case of any Old Notes owned by two or
more joint holders) on a Letter of Transmittal must correspond exactly with the
name(s) appearing on the records of the Registrar.

     6.   Records.  The Exchange Agent shall maintain, on a continuing basis, in
addition to the information required by Paragraphs 3 and 4 hereof, a record
showing the following:  (i) the names and addresses of all Holders who have
tendered Old Notes for exchange and of all Holders to whom New Notes will be or
have been issued or to whose DTC account New Notes will be or have been
credited, (ii) the face amount of Old Notes held by each such Holder, and (iii)
the face amount of Old Notes tendered by, and New Notes to be issued to, each
such Holder.  Upon the request of IMPSAT, the Exchange Agent shall provide
IMPSAT with a report setting forth the information maintained pursuant to this
Paragraph 6, together with such other information as may from time to time be
reasonably requested.


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     7.   Fees.  IMPSAT shall pay all reasonable out-of-pocket expenses of the
Exchange Agent for postage, stationery, printing, telephone, facsimile, telex
and other similar items (other than those specifically described below) and the
reasonable fees and disbursements of legal counsel to the Exchange Agent
incurred in rendering services hereunder at cost, pursuant to monthly invoices
from the Exchange Agent.  Except with respect to Section 10 hereof, in no case,
however, unless agreed to in advance by IMPSAT, shall the payment by IMPSAT of
the fees and disbursements of legal counsel to the Exchange Agent exceed the
sum of $5,000.  In addition, IMPSAT shall pay such fees as IMPSAT and the
Exchange Agent may agree in writing from time to time.

     8.   Limitation of Duties.  As Exchange Agent hereunder the Exchange Agent:

          (a)  shall have no duties or obligations other than those specifically
set forth herein;

          (b)  will be regarded as making no representations and having no
responsibilities as to the validity, sufficiency, value or genuineness of any
Old Notes or New Notes or any Letter of Transmittal or other document deposited
with or delivered to the Exchange Agent hereunder or any signature or
endorsement in connection therewith and will not be required to and will not
make any representation as to their validity, value or genuineness;

          (c)  shall not be obligated to take any legal action hereunder which
might in the judgment of the Exchange Agent involve any expense or liability
unless the Exchange Agent shall have been furnished with indemnity acceptable to
it;

          (d)  may rely on and shall be protected in acting in good faith
reliance upon any certificate, instrument, opinion, notice, letter, telegram or
other document or security delivered to the Exchange Agent believed by it in
good faith to be genuine and to have been signed by the proper party or parties;

          (e)  shall not be liable for any action taken or omitted by the
Exchange Agent, or any action suffered by it to be taken or omitted, without
gross negligence, bad faith or willful misconduct on its part, by reason of or
as a result of the administration of its duties hereunder, and it may rely on
and shall be protected in acting in good faith reliance upon the written
instructions of any person believed by it in good faith to be a proper officer
or representative of IMPSAT relating to the Exchange Agent's duties hereunder;

          (f)  may apply to IMPSAT for written instructions with respect to any
matter arising in connection with the Exchange Agent's duties and obligations
arising under this Agreement, and the application by the Exchange Agent for
written instructions from IMPSAT may, at the option of the Exchange Agent, set
forth in writing any action proposed to be taken or omitted by the Exchange
Agent


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with respect to its duties or obligations under this Agreement and the date or
dates on or after which such action shall be taken, and the Exchange Agent
shall not be liable for any action taken or omitted in accordance with a
proposal included in any such application on or after the date specified
therein (which date shall not, without IMPSAT's consent, be less than five
business days after IMPSAT is deemed to have received such application) unless,
prior to taking or omitting any such action, the Exchange Agent has received
written instructions from IMPSAT in response to such application specifying the
action to be taken or omitted.  The right conferred by this Paragraph 8(f)
shall be restricted by the requirement of Paragraph 3 hereof that, with respect
to defects in any Letter of Transmittal or accompanying document, the Exchange
Agent shall take such steps as it shall deem reasonable and appropriate to
correct the same before applying to IMPSAT under this Paragraph 8(f) for
instructions; and

          (g)  may consult counsel satisfactory to the Exchange Agent and
IMPSAT, and the opinion of such counsel shall be full and complete authorization
and protection in respect of any action taken, suffered or omitted by it
hereunder in good faith and in accordance with the opinion of such counsel.

     9.   Court Orders.  If any property subject hereto is at any time attached,
garnished or levied upon under any court order or in case the payment,
assignment, transfer, conveyance or delivery of any such property shall be
stayed or enjoined by any court order, or in case any order, judgment or decree
shall be made or entered by any court affecting such property or any part
thereof, then and in any such event the Exchange Agent is authorized, in its
sole discretion, to rely upon and comply with any such order, writ, judgment or
decree which it is advised by legal counsel of its own choosing is binding upon
them, and, if it complies with any such order, writ, judgment or decree, it
shall not be liable to any of the parties hereto or to any other person, firm
or corporation by reason of such compliance even through such order, writ,
judgment or decree may be subsequently reversed, modified, annulled, set aside
or vacated.

     10.  Indemnification.  IMPSAT agrees to indemnify the Exchange Agent and
hold it harmless from and against any loss, liability or expense (including
reasonable counsel fees and expenses) incurred by the Exchange  Agent without
gross negligence, bad faith or willful misconduct on its part arising out of or
in connection with the administration of its duties and any action taken or
omitted to be taken hereunder and otherwise in connection with the Exchange
Offer and against any stock transfer or other tax.

     11.  Amendments.  This Agreement may be amended only by an instrument in
writing executed by the parties hereto or their successors and assigns.

     12.  Reports; Notices.  All reports, notices, applications (including
applications for instructions in accordance with Paragraph 8(f) hereof) and
other communications required or permitted hereunder shall be in writing and
shall be deemed given when addressed and delivered by facsimile transmission
(confirmed by telephone call), which delivery may be followed by delivery by
hand or


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overnight delivery service, to the address for the party set forth below or at
such other address as a party may furnish by like notice to the other parties
hereto:

          If to IMPSAT:

          IMPSAT Fiber Networks, Inc.
          Alferez Pareja 256
          1107 Buenos Aires, Argentina
          Attn:  Mr. Guillermo Jofre, Chief Financial Officer
          Facsimile Number:  (5411) 4300-4007

          with a copy to:

          Arnold & Porter
          555 12th Street, N.W.
          Washington, D.C.  20004
          Attn:  Neil M. Goodman, Esq.
          Facsimile Number:  (202) 942-5999

          If to the Exchange Agent:

          The Bank of New York
          101 Barclay Street
          Floor 21 West
          New York, New York  10286
          Attn:  Global Finance Unit
          Facsimile Number:  (212) 815-4803

     Delivery of a notice sent by facsimile transmission shall be deemed to be
effective 24 hours after delivery has been confirmed by telephone.

     13.  Counterparts.  This Agreement may be executed in counterparts, each
of which shall be deemed to be an original but both of which together shall
constitute but one agreement.

     14.  Termination.  This Agreement shall terminate on [December 31, 2000],
or on such earlier date as may be agreed in a signed writing between IMPSAT and
the Exchange Agent.  Upon termination, copies of all information maintained by
the Exchange Agent for IMPSAT under this Agreement shall be delivered to IMPSAT
as soon as practicable following IMPSAT's request for such information.  The
right of the Exchange Agent to be reimbursed for out-of-pocket expenses as
provided in Paragraph 7 and the indemnification provisions of Paragraph 10
hereof shall survive termination of this Agreement.

     15.  Governing Law.  This Agreement shall be governed by and construed in
accordance with the laws of the State of New York.



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     IN WITNESS WHEREOF, IMPSAT Fiber Networks, Inc. and The Bank of New York
have duly executed this Agreement as of the date first set forth above.



                                        IMPSAT FIBER NETWORKS, INC.




                                        By: _____________________________
                                        Name:     Guillermo Jofre
                                        Title:    Chief Financial Officer





                                        THE BANK OF NEW YORK



                                        By: _____________________________

                                        Name:     Thomas Tabor
                                        Title     Assistant Vice President



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