AGREEMENT

This AGREEMENT is entered by and between:

         MASTEC,  INC., a company  organized and existing  under the laws of the
         State of Florida,  United  States of America,  with head office at 3155
         N.W. 77th Avenue, in the city of Miami, State of Florida, United States
         of  America,  and/or  any  of  its  affiliated  companies  (hereinafter
         referred to as "MasTec"), and

         INEPAR, S.A. - INDUSTRIA E CONSTRUCOES, a company organized and 
         existing under the laws of Brazil, with head office at Av. Jusceline K.
         De Oliveira, no. 11.400, Cidade Industrial, in the city of Curitiba, 
         State of Parana, Brazil (hereinafter referred to as "Inepar"),

         (hereinafter jointly referred to as "Parties"@).

WHEREAS

This Agreement is based on the following:

A.       MasTec and Inepar  executed an Agreement of Intent,  dated May 17, 1997
         (hereinafter  referred to as "Agreement"),  providing for the terms and
         conditions  to  organize a Brazilian  corporation,  with the purpose of
         operating  in the  Brazilian  market of  rendering  of services for the
         introduction of  telecommunication  systems,  and which stocks would be
         100% (one hundred per cent) held by the Parties.

B.       Inepar, organized on June 26, 1997, a corporation under its control, 
         named MasTec Inepar, S.A.- Sistemas de Telecomunicacoes, with head
         office at Avenida Jusceline K. De Oliveira, no. 11.400-CIC, in the city
         of Curitiba, State of Parana, Brazil, with acts of incorporation filed 
         with the Most Worthy Commercial Registry of the State of Parana, 
         Brazil, under no. 41300045739, in session held on July 01, 1997 
         (hereinafter referred to as ("Corporation"), in order that, in the 
         future and in accordance with the Agreement, the Corporation carried 
         out a capital increase to allow the admittance of the new stockholder 
         MasTec (hereinafter referred to as "Capital Increase"), and as of the
         Capital Increase, referred to as "Newco"




























































































































































































Taking into  consideration  the terms of the  Agreement of Intent and its mutual
commitments stipulated herein, the Parties agree to execute this Agreement to be
governed by the following clauses and conditions:

I - THE CORPORATION

1.       The corporation  capital is currently composed of 100,000 (one hundred)



         common  nominative  stocks,  in that Inepar  holds  99.50% of its total
         capital: 
         1.1 Newco shall be a corporation governed by the provisions of
         its articles of organization (hereinafter referred to as "Articles of 
         Organization") and by the  applicable laws, in that all of its existing
         stocks and each and  every stock to be  issued  in the  future shall be
         subject to the terms and conditions of this Agreement.

2.       Inepar transferred the Corporation all backlog - with the respective 
         accounting on June 30, 1997 - of its agreement:

(i)      -    PI 5148 with Telrj, dated June 30, 1996;
(ii)     -    PI 5152 with Equitel, dated February 17, 1997;
(iii)    -    PI 5153 with Telepar, dated March 11, 1997;
(iv)     -    PI 5154 with Telepar, dated January 31, 1997;
(v)      -    PI 5155 with Telesp, dated December 31, 1996;
(vi)     -    PI 5156 with Telesp, dated December 31, 1996;
(vii)    -    PI 5157 with Motorola, dated March 11, 1997;
(viii)   -    PI 5158 with Telesp, dated May 30, 1997;
(ix)     -    PI 5159 with Telesp, dated June 23, 1997;
(x)      -    PI 5160 with Telepar, dated April 01, 1997, and
(xi)     -    PI 5161 with Alcoa,  dated June 20, 1997,  (hereinafter  jointly
              referred to as "Transferred Agreements").

Inepar shall also transfer the Corporation the Agreements  which on the occasion
of this Agreement are under negotiation with the customers:

(i)       Motorola - Telepar - South  Region, valued estimated at 
          US $32,000,000.00 (thirty two million US dollars); 
(ii)      Consorcio  Globaltelecom - Band E. Value estimated at 
          US $100,000,000.00 (one hundred million US dollars)and
(iii)     Telepar  -  infrastructure  for  the  conventional  telephony, value
          estimated at US $9,000,000.00  (nine million US dollars), (hereinafter
          jointly referred to as "Agreements to be Transferred").

The  Transferred  Agreements  together  with the  Agreements  to be  Transferred
represent a total backlog of approximately the equivalent in Brazilian  currency
to US  $370,000,000.00  (three hundred seventy million US dollars),  in that the
Agreements to be Transferred  shall be  automatically  incorporated  to Newco by
Inepar on the occasion of their definite execution.






         2.1      Inepar  shall  gear its best  efforts  with its  customers  to
                  approve the transfer of the Transferred  Agreements and of the
                  Agreements to be Transferred to Newco. In the event the status
                  of minority of Inepar in Newco causes any  impediment  for the
                  presentation  of the  Agreements  at Newco,  the Parties shall
                  consider,  among others,  the  alternative to subcontract  the
                  purpose of the Transferred Agreements and of the Agreements to
                  be  Transferred  to Newco and/or  present  Newco the Backlog -
                  with  the  respective  accounting  - of  other  agreements  or
                  services for Inepar and/or of any of its subsidiary  companies
                  in order to perform the amount of the invoicing and respective
                  margins of  profitability  which  arise out of the  agreements
                  herein referred to above.

II.      CAPITAL INCREASE

3.       The Parties agree that at July 31, 1997 (hereinafter referred to as 
         "capital increase date") Inepar, company's majority stockholder, will
         carry out a Special Stockholders' Meeting, recording its respective
         Minutes with the purpose of: (i) increasing the corporate's capital so 
         as to allow the admittance of the new stockholder MasTec, 
         (ii) transferring the head office of Newco from Curitiba (State of 
         Parana) to Sao Paulo (State of Sao Paulo) and (iii) issuing new common
         stocks of Newco (the "Stocks"), which shall be subscribed and paid in 
         by MasTec representing fifty-one per cent (51%) of Newco's total 
         capital (hereinafter referred to as "Subscription").  The Subscription 
         shall be preceded by the guarantee statements issued by Inepar pursuant
         to item iv hereof.

         3.1      MasTec  shall  transfer,  in  cash  the  amount  in  Brazilian
                  currency equivalent to us$ 29,400,000.00  (twenty-nine million
                  four  hundred  thousand  US  dollars)  in  order to pay up the
                  Stocks.  Such value shall be paid in eleven (11)  installments
                  in that the first  installment  shall be paid,  at the Capital
                  increase Date, in the value, in Brazilian currency, equivalent
                  to US$ 5,000,000.00 (five million US dollars), followed by ten
                  (10) equal  monthly  installments  in the value,  in Brazilian
                  currency,  equivalent  to US$  2,440,000.00  (two million four
                  hundred forty thousand US dollars).

4.       MasTec  will pay  Inepar,  at the  Capital  Increase  Date,  a goodwill
         equivalent to two hundred  fifty  thousand  (250,000)  common stocks of
         MasTec  and an option to acquire  fifty  thousand  (50,000)  additional
         common  stocks of MasTec at the NYSE  closing  market  price on May 16,
         1997, for a term of up to ten (10) years.

5.       Newco's stock  composition,  once the Subscription is carried out, will
         be  fifty-one  per cent (51%) of the  stocks to MasTec  and  forty-nine
         percent  (49%)  of  the  stocks  to  Inepar,  in  order  to  allow  the
         consolidation   and  merger  of  Newco  results,   in  Brazil,  in  the
         accounting-financial  structure  of  MasTec  in the  United  States  of
         America.

III - OPERATION CONDITIONS

6.       On the Capital  Increase Date,  Inepar will provide and transfer to the
         Company all documents  needed for the operation of the  Corporation  in
         the   field   of   rendering   of   services   of    introduction    of
         telecommunications systems.

7.       After the Capital  Increase  Date,  possible  acquisitions  of regional
         companies will be analyzed aiming for the best Brazilian  market share;
         in that the first company to be analyzed for such purposes will be CIDE
         ENGEHARIA  LTDA.,  with head office in the city of  Curitiba,  State of
         Parana, Brazil.






IV - GUARANTEES AND REPRESENTATIONS

8. Inepar states the following:

         (A)   the legal  existence and regular operation and functioning of the
               Controlled   Corporation;   
         (B)   the  validity  and  effectiveness of transferred  Agreements and
               Agreements  to be  Transferred;  
         (C)   the nonexistence of any labor, fiscal or social security demand
               against the Controlled Corporation, and the nonexistence of any 
               liens regarding the properties and assets of the Controlled 
               Corporation;
         (D)   the net equity position of Controlled  Company is reflected in
               the  balance  sheet of the  Capital  increase  Date,  attached
               hereto as Annex 8 (D); and
         (E)   the nonexistence of any liabilities or contingencies not 
               disclosed in said Annex 8 (D).

V - NEWCO'S MANAGEMENT

9.       After the Capital  Increase  date,  the Parties  agree that Newco shall
         have a Management  Committee  formed by up to five (5)  members,  among
         those it will  necessarily  be the  President  Director  of Newco.  The
         Management  Committee  shall be formed as  follows:  (i) one (1) member
         named Chairman, appointed by mutual agreement between the Parties; (ii)
         two (2) members simply named Committee Members appointed by MasTec; and
         (iii) other two (2) members simply named Committee Members appointed by
         Inepar.  The powers of said  Committee  Members  will be defined in the
         Articles of Organization.

         9.1      In case of  temporary  impediment,  the  Chairman  himself may
                  appoint  another  Member to substitute for him, and in case of
                  definitive   vacancy  the  Parities  will  choose,  by  common
                  agreement,  another  Chairman  who will be in office until the
                  end of the tenure.

         9.2      In case of vacancy or  definitive  impediment of nay Committee
                  Member,  the  Party  which has  appointed  said  Member  shall
                  appoint a substitute who will complete the  performance of the
                  tenure of the substituted Member.

10.      Newco shall have a Board of Directors  formed by up to five (5) members
         as follows;  (i) one (1) member named President  Director  appointed by
         mutual agreement of the Parties, who will also be necessarily appointed
         for one of the office of the Company's Management  Committee;  (ii) tow
         (2) members named individually  Executive  Vice-President  Director and
         Commercial  Director  appointed  by President  Director;  (iii) one (1)
         member named Financial  Managing Director appointed by MasTec; and (iv)
         one (1) member named Technical Director appointed by Inepar. The powers
         of said Directors will be defined in the Articles of Organization.






         10.1     In case of vacancy or  definitive  impediment of any Director,
                  the party or the President  Director who appointed him, as the
                  case  may be,  shall  appoint  a  substitute  who will end the
                  tenure of the substituted Director.

         10.2     Newco's President Director shall have all the necessary powers
                  to carry out the Company's management.

         10.3     In   Newco's    President    Director    absence,    Executive
                  Vice-President Director,  jointly with any other Director, may
                  perform the President Director's duties.

         10.4     The  Parties  agree that,  as  stockholders  of Newco,  MasTec
                  and/or Inepar, as the case may be, they may grant and assign a
                  sole  stock held by them to  natural  individuals  who come to
                  form the  Management  Committee  of Newco,  in order to comply
                  with the legal demand related to the member of such board. The
                  stocks then  disposed of shall be  encumbered  in favor of the
                  respective  assignor  stockholders.  It is also  agreed  that,
                  should any of said natural  individuals fail to participate in
                  Newco's Management Committee,  the stocks shall be immediately
                  assigned to the respective assignor  stockholder,  who will be
                  fully in charge of such obligation fulfillment.

VI       NOTICES

11.      Any notices  shall be given,  as provided for herein,  in writing,  and
         will be effective upon its receipt, if sent by registered air mail, and
         in case the notice is sent by fax it will be effective  when  confirmed
         by the original copy sent via  registered air mail, to the Party at the
         address indicated  hereinbelow or at another address, as said Party may
         indicate, by means of written notice pursuant to the provisions of this
         Section.

To MasTec:                                  To Inepar:
Attention:                                  Attention: Di Marco Pozzo
Fax No.:                                    Fax No.: ++ 55 41 341 1414

VII - MISCELLANEOUS

12.      This Agreement  shall be effective for a period of ten (10) years as of
         the present date or, whenever  observed that time limitation  meanwhile
         no changes in the original share of Newco's  stockholders occur, and in
         such  case,  if none of them  delivers  a notice  informing  about  its
         determination  not to consent  with its  renewal  before the end of the
         ten-year term,  this Agreement  shall be renewed without any additional
         measure for an indefinite term.

         12.1     In case of decrease in Newco's original  interests,  the terms
                  of this Agreement shall be reviewed.






13.      The  Parties  may  validate  the  obligations   hereunder  by  specific
         performance or any other legal action,  including claim for damages, to
         which they have the right, under the applicable laws.

14.      The terms of this Agreement shall bind the parties to their  respective
         successors or  authorized  assignees.  No right or obligation  shall be
         granted or assigned  hereunder,  by any of the Parties,  without  prior
         written consent of the other Party.

15.      This  Agreement  represents  the full  agreement  between  the  Parties
         regarding  the matters  discussed  and shall prevail on all other prior
         related  settlements,   compromises,  and  documents.  Any  amendments,
         cancellation or renounce shall require a written document duly executed
         by the Parties.

16.      This  Agreement  will be ruled by Brazilian  laws.  Any disputes  which
         result from this Agreement shall be (first settled by arbitration), and
         then,  if necessary,  by the Courts of the city of Sao Paulo,  State of
         Sao Paulo, excluding any other, no matter how privileged it may be.

IN WITNESS WHEREOF, the Parties execute this Agreement in three (3) counterparts
before the two (2) undersigned witnesses.

                                            Sao Paulo, July 21, 1997

                                  MASTEC, INC.

- --------------------------                  ----------------------------
By:                                         By:
Title:                                      Title:

                       INEPAR S.A. INDUSTRIA E CONSTRUCOES


- --------------------------                  ----------------------------
By:      Atilano De Oms Sobrinho            By:      Mario Celso Petraglia
Title:   President                          Title:   Vice-President

Witnesses:

- --------------------------                  ----------------------------
By:                                         By:
RG:                                         RG







"SIDE LETTER"


Without any detriment of the provisions of the AGREEMENT executed between:

         MASTEC,  INC., a company  organized and existing  under the laws of the
         State of Florida,  United  States of America,  with head office at 3155
         N.W. 77th Avenue, in the City of Miami, State of Florida, United States
         of  America,  and/or  any  of  its  affiliated  companies  (hereinafter
         referred to as "MasTec"), and

         INEPAR, S.A. - INDUSTRIA E CONSTRUCOES, a company organized and 
         existing under the laws of Brazil, with head office at Av. Juscelino K.
         De Oliveria, no. 11.400, Cidade Industrial, in the city of Curitiba,
         State of Parana, Brazil (hereinafter referred to as "Inepar"),

         the  parties,   shareholders   of  MASTEC  INEPAR  S/A  -  SISTEMAS  DE
         TELECOMUNICACOES,  have established herewith that the decisions related
         to the matters  specified  hereafter shall be invariably made by mutual
         agreement:

a)   Amendments to the Articles of Organization of MASTEC INEPAR S/A -SISTEMAS 
     DE TELECOMUNICACOES related to:

         (i)      changes to the corporate purposes which determine, directly or
                  indirectly,  amendments to the  corporate  purpose of products
                  and services of the Corporation;

         (ii)     creation, amendment or extinction of types of shares or rights
                  related to the stocks;

         (iii)    creation of  beneficiary  parties or  debentures  convertibles
                  into stocks  and/or that have  interest in the profits,  or of
                  other  securities  which represent the interest in the capital
                  and/or in the results of the  Corporation  or even  securities
                  which  guarantee any rights of vote in the  administration  of
                  the Corporation;

         (iv)     definition and/or amendment to the fiscal year of the 
                  Corporation;

         (v)      amendments to the policy of dividends distribution of the
                  Corporation;

         (vi)     definition  and/or  amendment to the hypothesis of call of the
                  Statutory  Audit  Committee  as well as of the  number  of its
                  members;

b) - The following operational decisions:

         (i)      dissolution, liquidation, bankruptcy, reorganization or
                  suspension of the liquidation;

         (ii)     reorganizations   of   corporations,   such  as   mergers   or
                  consolidations and others which cause the creation,  amendment
                  and replacement of stocks or other  securities which represent
                  the  interest  in the  capital  and/or in the  results  of the
                  Corporation;





         (iii)    sale, acquisition or taxation of interest in any company which
                  competes with the  Corporation  or which capital also pertains
                  to a  competitor  of the  Corporation  or that holds  majority
                  interest in any company;

         (iv)     increase and/or reduction in the corporate capital of the 
                  Corporation;

         (v)      manufacture of new products  and/or  beginning of new projects
                  unrelated  to the  rendering  of services of  introduction  of
                  systems of telecommunications.