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                                                                    Exhibit 99.5

                           Harken Energy Corporation

                             Shares of Common Stock

                           Offered Pursuant to Rights

                        Distributed to Security Holders

                          of Harken Energy Corporation

_________________, 2002

To Our Clients:

         Enclosed for your consideration are a prospectus, dated
________________, 2002 (the "Prospectus"), and the "Instructions as to Use of
Harken Energy Corporation Rights Certificates" relating to the offering (the
"Rights Offering") by Harken Energy Corporation (the "Company") of shares of its
Common Stock (as defined below) pursuant to non-transferable subscription rights
(the "Rights") distributed to all holders of record of shares of its common
stock, par value $0.01 per share (the "Common Stock"), and shares of its Series
G1 preferred stock and shares of its Series G2 preferred stock (collectively,
the "Preferred Stock") at the close of business on ______________, 2002 (the
"Record Date"). The Rights are described in the Company's prospectus dated
_______________, 2002 (the "Prospectus").

         In the Rights Offering, the Company is offering an aggregate of
95,238,096 shares of its Common Stock (the "Underlying Shares"), as described in
the Prospectus.

         The Rights will expire, if not exercised, at 5:00 p.m., New York City
time, on ______________, 2002, unless extended in the sole discretion of the
Company (as it may be extended, the "Expiration Date").

         As described in the Prospectus, you will receive one Right for each
share of Common Stock owned (or in the case of Preferred Stock, one Right for
each share of Common Stock issuable upon conversion) of record as of the close
of business on the Record Date.

         Each subscription right will entitle you to purchase the number of
shares of Common Stock equal to $10 million, divided by the Subscription Price,
divided by ______________, the number of shares of common stock outstanding plus
the number of shares of common stock issuable upon conversion of the Series G1
preferred stock, and Series G2 preferred stock, on the Record Date (the
"Subscription Right"). The Subscription Price for the subscription rights will
equal 70% of the current market price of the common stock. The Company will
determine the current market price of the common stock by averaging the closing
price of the common stock on the American Stock Exchange for the five (5)
trading days immediately preceding the commencement of the offering, except the
current market price will be no greater than $0.50 per share or less than $0.15
per share.

         Lyford Investments Enterprises Ltd., a creditor of the Company, has
agreed to act as a standby underwriter in the offering and will purchase any and
all shares not subscribed for by other stockholders.

         The Rights will be evidenced by non-transferable Rights certificates
and will cease to have any

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value at the close of business on the Expiration Date.

         The materials enclosed are being forwarded to you as the beneficial
owner of Common Stock carried by us in your account but not registered in your
name. Exercises and sales of rights may be made only by us as the record owner
and pursuant to your instructions. Accordingly, we request instructions as to
whether you wish us to elect to subscribe for any shares of Common Stock to
which you are entitled pursuant to the terms and subject to the conditions set
forth in the enclosed Prospectus. However, we urge you to read the document
carefully before instructing us to exercise your Rights.

         Your instructions to us should be forwarded as promptly as possible in
order to permit us to exercise Rights on your behalf in accordance with the
provisions of the Rights Offering. The Rights Offering will expire at 5:00 p.m.,
New York City time, on the Expiration Date. Once you have exercised the
Subscription Right, such exercise may not be revoked.

         If you wish to have us, on your behalf, exercise the Rights for any
shares of Common Stock to which you are entitled, please so instruct us by
completing, executing and returning to us the instruction form on the reverse
side of this letter.

             Any questions or requests for assistance concerning the
              Rights Offering should be directed to American Stock
                            Transfer & Trust Company,
                   the Subscription Agent, at (718) 921-8237.

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                         Beneficial Owner Election Form

                                  Instructions

         The undersigned acknowledge(s) receipt of your letter and the enclosed
materials referred to therein relating to the offering of shares of common stock
(the "Common Stock") of Harken Energy Corporation (the "Company").

         This will instruct you whether to exercise Rights to purchase shares of
the Company's Common Stock distributed with respect to the shares of the
Company's Common Stock held by you for the account of the undersigned, pursuant
to the terms and subject to the conditions set forth in the Prospectus and the
related "Instructions as to Use of Harken Energy Corporations Rights
Certificates."

         Box 1. [_]  Please DO NOT EXERCISE RIGHTS for shares of Common Stock.

         Box 2. [_]  Please EXERCISE RIGHTS for shares of Common Stock as set
forth below.

                             Number of     Subscription
                              Rights           Price       Payment
                           -------------  -------------  -----------
Subscription Right                      x              =


         Box 3. [_]  Payment in the following amount is enclosed
                     $_________________. (This amount must equal the amount set
                     forth under "Payment" above).

         Box 4. [_]  Please deduct payment from the following account maintained
                     by you as follows:

_________________________               ________________________________________
     Type of Account                                  Account No.

                                        $_______________________________________
                                        ________________________________________
                                        ________________________________________
                                        Signature(s)

                                        Please type or print name(s) below:
                                        ________________________________________
                                        ________________________________________


Date:  _____________________, 2002

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