EXHIBIT 4.3
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                              METHANEX CORPORATION

                             STOCK OPTION PLAN 2006


A.      THE PLAN

        The Stock  Option Plan 2006 (the  "Plan") is the  amended and  restated
stock  option  plan  of  Methanex   Corporation   ("Corporation"),   reflecting
amendments to and including  March 3, 2006, of the prior Incentive Stock Option
Plan.  The Plan for key  employees  and  directors of the  Corporation  and its
majority-owned subsidiaries ("subsidiaries") to purchase unissued common shares
("Shares") of the Corporation is hereby established on the terms and conditions
hereinafter set out.

B.      PURPOSE

        The purpose of the Plan is to develop the interest of key employees and
directors of the Corporation and its  subsidiaries in growth and development by
providing  them with the  opportunity  through  options on Shares to acquire an
increased financial interest in the Corporation.

C.      GRANT OF OPTIONS

        The Board of Directors of the  Corporation may from time to time in its
discretion grant to officers,  directors and other employees of the Corporation
and its subsidiaries (who in each case must be full-time employees or directors
of the  Corporation  or a  subsidiary  and who,  in the opinion of the Board of
Directors,  are key  employees or  directors),  an option to acquire all or any
part of an  allotment  of Shares of the  Corporation  upon and  subject to such
terms,  conditions and limitations as are herein contained and otherwise as the
Board of Directors may from time to time determine with respect to each option.

        The  maximum  number of Shares that may be issued from and after May 2,
2006  pursuant  to options  granted  pursuant  to this Plan is  5,250,000.  The
maximum  number of Shares  which may be reserved for issuance to, or covered by
any  option  granted  to,  any  person  shall not exceed the lower of 5% of the
outstanding issue or the maximum number permitted by the applicable  securities
laws and  regulations  of  Canada  or of the  United  States  or any  political
subdivision  of either,  and the by-laws,  rules and  regulations  of any stock
exchange or other trading  facility upon which the Shares are listed or traded,
as the case may be.

D.      EXERCISE PRICE

        The price of the Shares, upon exercise of each option granted under the
Plan,  shall be a price  fixed for such option by the Board of  Directors,  but
such price  shall be not less than the fair  market  value of the Shares on the
date the option is granted.  The fair market  value for this  purpose  shall be
deemed to be the US Dollar  equivalent of the closing price at which board lots
of the  Corporation's  Shares were traded on the Toronto Stock  Exchange on the
day  preceding  the date on which the option is granted or if no board lots are
traded on such day then the US Dollar  equivalent of the closing price at which
board lots were traded on the most recent day upon which at least one board lot
was traded on such  Exchange.  The "US Dollar  equivalent of the closing price"
shall be  determined  using the US  Dollar/Canadian  Dollar  Daily Noon Rate as
published  by the Bank of  Canada  on the same  day that the  closing  price is
established.



E.      TERM

        The Shares  identified  in the option may be  purchased at such time or
times  after  the  option  is  granted  as may be  determined  by the  Board of
Directors.

        Each option,  unless sooner  terminated  in accordance  with the terms,
conditions  and  limitations  of the option,  shall  expire on a date  ("Expiry
Date") not later than ten years from the day the option was granted, which date
shall be fixed by the Board of Directors,  except that, subject to the right of
the Board of  Directors,  in its  discretion,  to  determine  that a particular
option may be exercisable during different  periods,  in respect of a different
amount or portion of shares or in a different manner:

        (a)     in the case of the  death of an  optionee  prior to the  Expiry
                Date,   the   option   will  be   exercisable   by  the   legal
                representative of such optionee, or by the person or persons to
                whom the optionee's rights under the option pass by will or the
                laws of devolution or  distribution  and descent,  prior to the
                earlier  of (i) the date  which  is one  year  from the date of
                death of such optionee (or such shorter or longer period as may
                be determined by the Board of Directors at the time of grant of
                the option), and (ii) the Expiry Date;

        (b)     if the optionee ceases,  for any reason other than death, to be
                a  director,  officer  or  employee  of  the  Corporation  or a
                director,   officer  or  employee  of  a   subsidiary   of  the
                Corporation  prior  to the  Expiry  Date,  the  option  will be
                exercisable  by the  optionee  prior to the  earlier of (i) the
                date which is one year from the date such optionee so ceases to
                be a  director,  officer or employee  of the  Corporation  or a
                director,   officer  or  employee  of  any  subsidiary  of  the
                Corporation,  or such shorter or longer  period as the Board of
                Directors may, in its discretion, determine and (ii) the Expiry
                Date.

        The retirement of any optionee who is a director of the  Corporation or
any subsidiary at any general  meeting of the Corporation or such subsidiary as
required by the constating  documents of the Corporation or the subsidiary,  as
the case may be, will not result in the  termination  of the option  granted to
such  optionee  provided  that such optionee is re-elected at such meeting as a
director of the Corporation or of such subsidiary, as the case may be.

        A change in the duties or position  of an  optionee or the  transfer of
such  optionee  from a  position  with the  Corporation  to a  position  with a
subsidiary of the Corporation,  or VICE VERSA, will not trigger the termination
of such optionee's option,  provided such optionee remains a director,  officer
or  employee  of the  Corporation  or a  director,  officer or  employee of any
subsidiary of the Corporation.

        Shares  subject  to an  option  which  is not  exercised  or  which  is
cancelled shall become available for subsequent options under the Plan.

F.      ISSUE OF SHARES

        No person shall have any of the rights of a  shareholder  in respect of
any Shares  under an option  until such  shares  have been paid for in full and
issued to such person.



G.      TRANSFERABILITY

        No option shall be transferable or assignable otherwise than by will or
the laws of succession and distribution.

H.      ALTERATION OF NUMBER OF SHARES SUBJECT TO THE PLAN

        The  number  of  Shares  subject  to the  Plan  shall be  increased  or
decreased  proportionately  in the event of the subdivision or consolidation of
such  Shares  of the  Corporation,  and  in  any  such  event  a  corresponding
adjustment  shall be made  changing the number of shares  deliverable  upon the
exercise of any option  theretofore  granted  without change in the total price
applicable to the unexercised  portion of the option,  but with a corresponding
adjustment in the price for each share covered by the option. In the event that
the Corporation is reorganized or merged or  consolidated  or amalgamated  with
another corporation,  appropriate  provisions shall be made for the continuance
of the  options  outstanding  under the Plan and to prevent  their  dilution or
enlargement.

I.      ADMINISTRATION

        Within the  limitations  set forth in the Plan, the Board of Directors,
or any Committee of the Board to which such authority shall be delegated by the
Board,  is  authorized to provide for the grant and exercise of options on such
terms (which may vary as between options) as it shall determine.  All decisions
and  interpretations  made by the Board of  Directors,  or any such  committee,
shall be binding and conclusive on the Corporation  and all employees  eligible
to participate in the Plan.

J.      AMENDMENT AND TERMINATION

        The Board of Directors may at any time  terminate the Plan with respect
to any Shares not at the time subject to option, and the Board of Directors may
at any time amend any of the  provisions  of the Plan subject to obtaining  any
required  approval  of the  appropriate  stock  exchange  or  other  regulatory
authority but any such amendment may not,  without the consent of the optionee,
adversely affect or impair any option  previously  granted to an optionee under
the Plan.