Exhibit 10.27
                                 -------------


                           CARRIER SERVICES AGREEMENT


         This Carrier  Services  Agreement  ("Agreement") is executed on May 22,
2003 (the "Effective  Date") between ATSI  Communications,  Inc.  (Delaware),  a
Delaware  corporation,  hereinafter  referred to as  ("Customer")  and Operadora
Mexicana de Telefonia, S.A. de C.V. (Omtel) and DIALMEX, L.LC, (Dialmex) a Texas
corporation , hereinafter collectively referred to as ("Provider(s)").

         WHEREAS,  Provider(s)  desire to  provide  telecommunications  services
and/or telecommunications  facilities to Customer ("Services"),  as described in
Addendum A and B attached hereto; and

         WHEREAS,  Customer desires to receive such Services,  and has requested
that the Provider(s)  provide such Services in accordance with the terms of this
Agreement.

         NOW THEREFORE,  in  consideration  of the mutual premises and covenants
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the undersigned agree as follows:

         1.  Services.  Provider(s)  agree to furnish to Customer,  and Customer
agrees to accept,  upon the terms and conditions set forth herein,  the Services
set forth in Addendum A. All Addendums  identified  herein are  incorporated  by
reference and specifically made a part of this Agreement.

         2. Duration.  The Term of this  Agreement  shall be for three (3) years
commencing on the Effective Date. This Agreement shall  automatically be renewed
for  additional  successive  one (1) year  terms  and shall  run  concurrent  in
accordance  with the  Shareholder  Agreement  executed on May 20,  2003  between
Telemarketing, S.A. de C.V. and ATSI Communications,  Inc. (Delaware) or as long
as Providers remain partners in ATSI Comunicaciones, S.A. de C.V. ("ATSICOM").


         3. Rates.  During the Term of this Agreement,  charges for the Services
shall be as set forth in Addendum A . The  Parties  hereby  agree that  Customer
shall receive  preferential  rates as those provided by Omtel to Dialmex.  These
Rates are those of Omtel's cost and can be adjusted  upon at least five (5) days
prior written  notification to Customer without requiring any other signature of
the parties hereto acknowledging and agreeing to the same.

         4. Invoices.  The parties acknowledge that all invoices for traffic are
processed  every  seven days on a per MINUTE  basis.  Dialmex  will  prepare and
deliver to Customer an invoice for Services  provided  ("Payable  Amount") every
seven days to  Customer,  which  shall be paid within the next three (3) working
days after receiving such invoice via wire transfer.  If the full Payable Amount
is not received by Dialmex within the next three (3) working days after Customer
has received such invoice, then Dialmex shall be able to temporarily suspend the
Services  until  payment is received.  On a monthly  basis,  Dialmex  shall also
invoice  Customer for the monthly E-1 charges as established in Addendum  and/or
B, if applicable.

                                       1
<PAGE>

         Should  Customer  default in payment for  Services,  then the  Customer
agrees that Services provided may be terminated as provided in this Agreement.

         Dialmex agrees to provide  Customer  real-time  access to its reporting
system for the purpose of accessing  and/or  downloading all Call Detail Records
(CDR).

         5. Security  Deposit.  To initiate  service,  Customer shall prepay the
estimated  usage per E-1 of termination for fifteen (15) days period in the form
of Cash or Letter of Credit as  established  in Addendum A.  True-up  will occur
every fifteen days between DialMex and the Customer; if the usage increases over
the fifteen (15) days estimated traffic prepayment,  Customer agrees to increase
the  prepayment or Letter of Credit amount equal to the actual usage for fifteen
(15) days.

         Return  of  deposited  funds-  Upon  expiration  of the  term  of  this
agreement  and/or the  termination  of this  Agreement for cause or by desire of
either  party,  DialMex  shall return to Customer  any amounts on deposit  which
prove to be in excess of any and/or all of the amounts due and payable  pursuant
to the final  invoice  and/or  reconciliation  of the  Customer's  account  with
DialMex  for the  Services  provided  to the  Customer  by and/or  through  this
agreement.

         6. IVA  Reimbursement.  DialMex and/or Omtel hereby agrees to reimburse
Customer  the total  amount  invoiced  corresponding  to IVA  (Impuesto al Valor
Agregado) be it 10% or 15% or any other  percentage  if changes occur in the Tax
Laws of Mexico until  Telemarketing  de Mexico,  S.A. de C.V. has  fulfilled its
obligations under the Share Purchase Agreement  executed between  Telemarketing,
ATSI Comunicaciones,  S.A. de C.V. and ATSI  Communications,  Inc. (Delaware) on
May 20, 2003. As soon as Telemarketing de Mexico, S.A. de C.V. has fulfilled its
obligations  set therein,  DialMex shall  reimburse  Customer 1/2 of all amounts
applicable to IVA.

         7. Disputes. Any billing discrepancies shall be presented to DialMex in
full detail, in writing,  within forty-five (45) days of the date of the invoice
in question.  Such notification should not relieve Customer of the obligation to
make all payments  including  the amounts  disputed by the due date set forth in
this agreement. DialMex shall not be obligated to consider any Customer disputes
which are received by DialMex more than  forty-five days (45) following the date
of the invoice in question. DialMex and Customer agree to use their best efforts
to resolve  the  dispute  in good  faith and  within  forty five (45) days after
DialMex  receives such notice.  If the disputed  amount is found to be valid,  a
credit will be issued to  Customer.  In the event that  DialMex and Customer are
unable to resolve  the  dispute  within this  forty-five  (45) day  period,  the
parties  consent to the  jurisdiction  of the Texas courts with venue at McAllen
for the purposes of this provision.

         8. Termination.  Except as otherwise provided herein, neither party may
terminate  this  Agreement  at any time  unless  either  Party  defaults  in the
performance of any of its material duties under this Agreement and does not cure
the default  within five (5) days after receipt of written notice from the other
party,  (ii) if either  Party admits  insolvency,  makes an  assignment  for the
benefit of its creditors,  is unable to pay debts as they mature,  has a trustee
or receiver appointed over all or a substantial portion of its assets, or enters
into an agreement for the extension or readjustment of all or substantially  all
of its obligations.

                                       2
<PAGE>

         9.  Remedies  Upon  Termination.  Upon  termination,  Customer will pay
within fifteen (15) days of such termination to Dialmex all outstanding invoices
and all charges for Services incurred. If such amounts are less than the Deposit
and/or Letter of Credit that Customer has provided to Dialmex, Dialmex agrees to
apply the Deposit  and/or  Letter of Credit and return to Customer any excess as
provided for in Section 5 of this Agreement.

         10.  Warranties.  The quality of Services  provided  hereunder shall be
consistent with industry  standards,  government  regulations and sound business
practices.  NEITHER PARTY MAKES ANY OTHER  REPRESENTATIONS  OR WARRANTIES TO THE
OTHER PARTY  ABOUT THE  SERVICES  PROVIDED  HEREUNDER,  EXPRESS OR  IMPLIED,  BY
OPERATION  OF LAW OR IN FACT,  INCLUDING,  WITHOUT  LIMITATION,  ANY WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

         11. Damages. UNDER NO CIRCUMSTANCES SHALL EITHER PARTY BE LIABLE TO THE
OTHER  PARTY OR ANY OF SUCH  OTHER  PARTY'S  CLIENTS  FOR  SPECIAL,  INCIDENTAL,
CONSEQUENTIAL  OR PUNITIVE  DAMAGES IN CONNECTION  WITH OR RELATED TO ANY OF THE
SERVICES  PROVIDED  PURSUANT  TO THIS  AGREEMENT,  WHETHER  OR NOT  THE  SERVICE
PROVIDER  RECEIVES  NOTICE OF ANY SUCH  DAMAGES AND WHETHER OR NOT SUCH  DAMAGES
COULD HAVE BEEN FORESEEN.

         12.  Force  Majeure.  Neither  party  shall be liable for any  failure,
interruption  and/or  diminution  of  Services  in the event that such  failure,
interruption  and/or  diminution  is the  result of any fire,  flood,  epidemic,
earthquake or any other act of God, explosion, strike or other disputes, riot or
civil  disturbance,  war (whether declared or undeclared),  armed conflict,  any
municipal ordinance,  or state or federal law, governmental order or regulation,
or order of any Court of competent  jurisdiction,  or other  similar  forces not
within the control of the Service providing party.

         13.  Assignment.  This Agreement shall be binding upon and inure to the
benefit of the  parties  hereto and their  respective  successors  and  assigns;
provided,  however,  that neither party may assign or transfer any of its rights
or obligations  hereunder  without the prior written consent of the other party,
such consent not to be unreasonably withheld or delayed.

         14.  Confidentiality.  Each party understands and agrees that the terms
and conditions of this Agreement and all non-tariff  documents referenced herein
are  confidential  between  Customer and Providers and shall not be disclosed by
either party to any other party.

         15.  Notices.  All notices given  hereunder and all payments to be made
hereunder shall be sent to the addresses set forth as follows:


                                       3
<PAGE>

         Customer:         8600 Wurzbach, Suite 700W
                           San Antonio, TX  78240
                           Tel:     210.614.7240
                           Facsimile:  210.614.7264

         Dialmex:




         Omtel:





or at such  other  addresses  as a party may  designate  in writing to the other
party.  All  notices,  requests,  consents and other  communications  under this
Agreement  shall be in writing and shall be deemed to have been delivered on the
date when hand  delivered or three (3) days after  deposit in the mail when sent
by U.S. Mail, postage prepaid,  by certified mail, return receipt requested,  or
telegraphed and confirmed,  or upon confirmation of sending when sent by fax, or
on the day after being sent when sent by overnight delivery service.

         16. Entire Agreement.  This Agreement contains the entire agreement and
understanding  of the  parties  hereto  and  supersedes  all  prior  statements,
representations, understandings or agreements of the parties with respect to the
subject matter contained herein.

         17. Amendment.  Except as otherwise provided herein,  including without
limitation  the party's  ability to make rate  changes as provided in Section 5.
above,  this Agreement shall not be amended,  changed,  modified,  terminated or
discharged  in whole or in part except by an instrument in writing duly executed
by the Parties or their approved successors or assigns.

         18.  Governing  Law.  This  Agreement is executed in Texas and shall be
governed  by the laws of the State of Texas,  with  exclusive  venue at McAllen,
Texas.

         19.  Indemnity.  The  Parties  agree to  indemnify  and hold the  other
Party's directors,  officers,  employees,  agents and advisors harmless from and
against any and all claims, demands, or actions and costs, liabilities or losses
arising  directly  or  indirectly  from the  Customer's  resale of the  Services
acquired by and/or through this agreement.

         20.  Interconnection.  The  Customer  agrees  to  interconnect  at such
locations indicated by Dialmex during the Term of this Agreement.

                                       4
<PAGE>

         IN WITNESS WHEREOF, the undersigned have set their hands.

ATSI Communications, Inc. (Delaware)                 Dialmex

By:    /s/ Arthur L. Smith                           By: /s/ Francisco Bunt
Name: Arthur L. Smith                                Name:  Francisco Bunt
Title: CEO                                           Title: CEO



                                Operadora Mexicana de Telefonia, S.A. de C.V.


                                By: /s/ Francisco Bunt
                                Name: Francisco Bunt
                                Title: CEO



                                       5
<PAGE>
                                   ADDENDUM A
                                DIALMEX SERVICES
                  TELECOMMUNICATION SERVICES AND/OR FACILITIES

         This Addendum is hereby  incorporated into the underlying  Agreement as
though an original part thereof.

Customer:                  ATSI Communications, Inc. (Delaware)

Address:                   8600 Wurzbach, Suite 700W
                           San Antonio, TX  78240


Primary Account Contact:

                  Legal & Billing:
                           Katie Keller
                           210.614.7240  Ext 1043
                           210.614.7264  Fax

                  Technical & Sales
                           Ruben Caraveo
                           210.614.7240 Ext.  1050
                           210.614.7264

Committed Capacity :  _____ E1's or DS3's  (___ )

Service: Termination to Mexico

Billing Increments: 1 minute increment
Deposit required per E1: $15,000.00USD

Rates (Mexico): this rates include TAX and are:
FOB N.Y., FOB DALLAS, SAN ANTONIO or MCALLEN, Texas.
SERVICE ALSO AVAILABLE FOB INTERNET (VOIP).

------------------------------------- --------------------------
           Billing Block                   Rate Per Minute
------------------------------------- --------------------------
  1  Mexico City                                $.015
------------------------------------- --------------------------
  2  Guadalajara, Monterrey                     $.015
------------------------------------- --------------------------
  3  Puebla, Leon, Toluca                       $.035
------------------------------------- --------------------------
  4                                            $.0467
------------------------------------- --------------------------
  5                                            $.0541
------------------------------------- --------------------------
  6                                            $.0583
------------------------------------- --------------------------
  Rest of country                              $.0998
------------------------------------- --------------------------

o All above rates FOB DIALMEX'S designated POP.
o CUSTOMER will be responsible for any charges incurred in running  ____ ( ) DS3
  or  _________ ( ) T1's to DIALMEX'S designated POP.
o CUSTOMER will provide compression equipment if needed.
o DIALMEX will provide 24 hrs. Technical support 7 days a week.


                                       6