Exhibit 5.1 COMPANY LETTERHEAD June 24, 2002 Halliburton Company 3600 Lincoln Plaza 500 North Akard Street Dallas, Texas 75201-3391 Ladies and Gentlemen: This opinion of counsel is given in connection with the preparation of the Registration Statement on Form S-8 (the "Registration Statement") to be filed by Halliburton Company (the "Company") with the Securities and Exchange Commission pursuant to the Securities Act of 1933, as amended. The Registration Statement relates to the offering, sale and delivery of an aggregate of up to 12,000,000 shares of the Company's common stock, par value $2.50 per share (the "Common Stock") and accompanying Preferred Stock Purchase Rights, pursuant to the Halliburton Company 2002 Employee Stock Purchase Plan (the "Plan"). Before rendering this opinion, I have examined such certificates, instruments and documents, including the Plan and copies of the relevant resolutions passed by the board of directors and stockholders of the Company. The Plan provides that the shares of Common Stock to be issued thereunder may be authorized but unissued Common Stock or Common Stock previously issued, reacquired and held in treasury by the Company. Based upon the foregoing examination and review, I am of the opinion that the shares of Common Stock to be issued pursuant to the Plan have been duly authorized and when the shares of Common Stock are issued and paid for in accordance with the terms of the Plan and any stock purchase right pursuant to which such shares may be issued under the Plan, such shares of Common Stock will be validly issued, fully paid and nonassessable and any related Preferred Stock Purchase Rights shall be validly issued. This opinion is rendered as of the effective date of the Registration Statement. I hereby consent to the filing of this opinion as an exhibit to the Registration Statement. Very truly yours, /s/ Bruce A. Metzinger Bruce A. Metzinger Senior Counsel and Assistant Secretary