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                                                                    Exhibit 10.1

                            RECIPROCAL LOAN AGREEMENT

                                                   In Seville, on April 20, 2004

                                    APPEARING

On the one hand, Mr. Jose Antonio Moreno Delgado, of legal age, inhabitant of
Seville, with domicile for these purposes at Avda. de la Buhaira, 2 and with
National Identity Document 00114321-B and Mr. Jose Marcos Romero, of legal age,
inhabitant of Seville, with domicile for these purposes at Avda. de la Buhaira,
2, and with National Identity document no. 27883847-G, for and on behalf of the
Company ABENGOA S.A. (hereinafter "Abengoa"), with registered office and address
for tax purposes in Seville, Avda. de la Buhaira, 2 recorded in the Mercantile
Register of said city, sheet 2921, folio 107, Company volume 47 and with
Corporate Tax Identification Code A- 41002288.

And on the other hand, Ms. Ana Maria Plaza Arregui, inhabitant of Madrid, of
legal age, with National Identity Document number 12374150-N, for and on behalf
of the Company TELVENT GIT, S.A. (hereinafter "Telvent"), with registered office
and address for tax purposes in Madrid, C/Valgrande 6, Company recorded in the
Madrid Mercantile Register, sheet M-257879, folio 164, Companies volume 15370,
with Corporate Tax Identification Code no. A- 82631623.

Hereinafter, Abengoa and Telvent shall jointly be referred to as the "Parties".

In the capacity in which they appear, they acknowledge that each other has the
necessary legal capacity to contract and be bound thereby on behalf of the
companies they represent

                                    RECITALS

Sole Recital.- By needs or convenience of cash flow and for the purposes of
               meeting financial commitments, and to take advantage of any
               surplus cash that both Parties may have whilst this Agreement
               is in force, the Parties have agreed to grant a reciprocal
               commercial loan, for the purposes of regulating their
               respective interests, pursuant to the following

                                     CLAUSES

One.-

Each of the Parties grants to and opens for the other Party, which accepts and
receives, a current account credit facility of up to a maximum amount of 45
MILLION EUROS (45,000,000 EUROS) or equivalent thereof in any other currency
admitted to trading on Spain's currency exchange.

Two.-

1. Drawdown of funds (hereinafter, Request for Funds) by ABENGOA shall be
subject to express approval by TELVENT. Once approval by TELVENT of the Request
for Funds has been obtained, ABENGOA shall communicate with sufficient advance
notice the planned

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date of the transaction so that it can be processed in due time and form.
Therefore, and except for occasional exceptions that shall be dealt with on an
individual basis, no Request for Funds received later than 1200 hrs on the
working day prior to the planned date of the transaction shall be dealt with.
The working timetable of Telvent in Madrid shall be used for the purposes of
determining working days.

2. Drawdown of funds (hereinafter, Request for Funds) by TELVENT shall be
subject to express approval by ABENGOA. Once approval by ABENGOA of the Request
for Funds has been obtained, TELVENT shall communicate with sufficient advance
notice the planned date of the transaction so that it can be processed in due
time and form. Therefore, and except for occasional exceptions that shall be
dealt with on an individual basis, no Request for Funds received later than 1200
hrs on the working day prior to the planned date of the transaction shall be
dealt with. The working timetable of Abengoa in Seville shall be used for the
purposes of determining working days.

3. The LENDER shall charge to the account of the BORROWER those amounts that the
latter draws down, paying into said account the payments that the latter makes
in repayment of the funds drawn down. The balance resulting on a daily basis in
the account shall accrue annual interest in favor of the LENDER equivalent to
the arithmetic mean of the EURIBOR INTEREST RATE AT ONE MONTH FOR LOANS IN EUROS
AND LIBOR AT ONE MONTH FOR THE REST OF CURRENCIES plus a differential of 0.75 %
and shall be calculated by the Hamburg method. Liquidation and payment of
interest shall be made at the end of each financial year and at the time the
loan matures.

4. If in turn the LENDER draws down (after giving the relevant advance notice)
funds of the BORROWER, said funds shall be applied first of all to offset any
credit balance held by the former and the surplus shall be deemed the balance
which, from that moment, it owes the above BORROWER, now becoming the LENDER.
The interest arrangements established in the previous paragraph shall be applied
to the above-mentioned balance.

Three.-

The final deadline for maturity of the loan is established as December 31, 2004.
However, this present Agreement shall be deemed automatically extended for
annual periods if, with one week's notice prior to the date of the initial
maturity or of the extension thereof, neither of the Parties gives notice in
writing of their intention to not extend it.

Four.-

THE BORROWER, whichever this may be at that time, may make early settlement of
the loan, fully or partially, without suffering for this reason any penalty.

Five.-

All rights of any kind, taxes, contributions and any expenses derived as a
result of this transaction shall be paid for by the Parties in proportion to the
amount and time for which they have been BORROWER. However, the BORROWER shall
pay for the expenses arising from any collection and enforcement procedure or
formality, if any.

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Six.-

Either of the Parties may terminate this Agreement in the following
circumstances:

a) Upon breach by the other Party of any of the clauses of this present
Agreement.

b) The Party that is at that time LENDER, in the event of any bill accepted from
the Party that is at that time BORROWER having been protested, or that any
judicial or administrative procedure has been instigated against the latter that
could give rise to seizure or attachment of its assets.

c) If the Party that is at this time the BORROWER files for suspension of
payments, creditors' arrangements, bankruptcy or public insolvency.

Any of the grounds for termination of this Agreement shall give rise to early
maturity of the loan automatically and without the need for advance notice, the
Party that is such time the LENDER being entitled to require performance of the
obligation or the termination of this present Agreement, without prejudice to
any other actions that may in law correspond to it.

Seven. -

The Parties agree that the clauses of this present Agreement shall apply, as
they are and inasmuch as they are relevant, to any loans and credit facilities
that have been granted by one to the other in advance of these proceedings,
producing novation and extinction thereof (novatorio extintivo).

Eight.-

The Parties, for any question that may arise in respect of interpretation,
fulfillment and/or execution of this Agreement subject themselves, waiving any
other forum that may correspond to them, to the courts and tribunals of Seville.

And in witness whereof and of their agreement with everything stated above, the
Parties sign this Agreement, in two counterparts, at the place and on the date
first indicated above.

For Abengoa, S.A.                                   For Telvent GIT, S.A.
/s/ Jose Antonio Moreno Delgado                     /s/ Ana Maria Plaza Arregui
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Signed: Mr. Jose Antonio Moreno Delgado             Ms. Ana Maria Plaza Arregui
/s/ Jose Marco Romero
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Signed: Mr. Jose Marcos Romero.