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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                              ---------------------

                                    FORM 11-K

                              ---------------------

                                   (MARK ONE)

[X]   ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF
      1934 (NO FEE REQUIRED)

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2003

                                       OR

[ ]   TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT
      OF 1934 (NO FEE REQUIRED)

            FOR THE TRANSITION PERIOD FROM _________ TO _____________

                          COMMISSION FILE NUMBER 1-8514

      A.    FULL TITLE OF THE PLAN AND THE ADDRESS OF THE PLAN, IF DIFFERENT
            FROM THAT OF THE ISSUER NAMED BELOW:

                               M-I RETIREMENT PLAN
                                 P.O. BOX 42842
                             HOUSTON, TX 77242-2842

      B.    NAME OF ISSUER OF THE SECURITIES HELD PURSUANT TO THE PLAN AND THE
            ADDRESS OF ITS PRINCIPAL EXECUTIVE OFFICE:

                            SMITH INTERNATIONAL, INC.
                    411 NORTH SAM HOUSTON PARKWAY, SUITE 600
                              HOUSTON, TEXAS 77060

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           INDEX TO FINANCIAL STATEMENTS AND SUPPLEMENTARY INFORMATION



                                                                           Page
                                                                           ----
                                                                        
Report of Independent Registered Public Accounting Firm                      3

Financial Statements:

   Statements of Net Assets Available for Plan Benefits
     as of December 31, 2003 and 2002                                        4

   Statement of Changes in Net Assets Available for
     Plan Benefits for the Year Ended December 31, 2003                      5

   Notes to Financial Statements                                             6

Supplemental Schedule:

   Form 5500, Schedule H, Part IV, Line 4i - Schedule of Assets
     (Held at End of Year) December 31, 2003                                10

Exhibit:

   23.1 - Consent of Independent Registered Public Accounting Firm          13



                                       2

             REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Administrative Committee of the
M-I Retirement Plan:

We have audited the accompanying statements of net assets available for plan
benefits of the M-I Retirement Plan (the "Plan") as of December 31, 2003 and
2002, and the related statement of changes in net assets available for plan
benefits for the year ended December 31, 2003. These financial statements are
the responsibility of the Administrative Committee. Our responsibility is to
express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company
Accounting Oversight Board (United States) and in accordance with generally
accepted auditing standards as established by the Auditing Standards Board
(United States). Those standards require that we plan and perform the audit to
obtain reasonable assurance about whether the financial statements are free of
material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements, assessing
the accounting principles used and significant estimates made by the
Administrative Committee, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, such financial statements present fairly, in all material
respects, the net assets available for plan benefits of the Plan as of December
31, 2003 and 2002, and the changes in net assets available for plan benefits for
the year ended December 31, 2003, in conformity with accounting principles
generally accepted in the United States of America.

Our audits were conducted for the purpose of forming an opinion on the basic
financial statements taken as a whole. The accompanying supplemental schedule of
assets (held at end of year) is presented for purposes of additional analysis
and is not a required part of the basic financial statements, but is
supplementary information required by the Department of Labor's Rules and
Regulations for Reporting and Disclosure under the Employee Retirement Income
Security Act of 1974. The schedule is the responsibility of the Administrative
Committee. Such supplemental schedule has been subjected to the auditing
procedures applied in our audit of the basic 2003 financial statements and, in
our opinion, is fairly stated in all material respects in relation to the basic
financial statements taken as a whole.

DELOITTE & TOUCHE LLP

Houston, Texas
June 21, 2004


                                       3

                               M-I RETIREMENT PLAN
              STATEMENTS OF NET ASSETS AVAILABLE FOR PLAN BENEFITS
                        AS OF DECEMBER 31, 2003 AND 2002




                                                                   2003                       2002
                                                                ------------               ------------
                                                                                     
ASSETS:
   Investments, at fair value                                   $198,297,643               $154,142,919
                                                                ------------               ------------
   Receivables-
     Company contributions                                         4,215,107                  1,979,270
                                                                ------------               ------------
NET ASSETS AVAILABLE FOR PLAN BENEFITS                          $202,512,750               $156,122,189
                                                                ============               ============


   The accompanying notes are an integral part of these financial statements.


                                       4

                               M-I RETIREMENT PLAN
         STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR PLAN BENEFITS
                      FOR THE YEAR ENDED DECEMBER 31, 2003


                                                                  
NET ASSETS AVAILABLE FOR PLAN BENEFITS AT DECEMBER 31, 2002          $156,122,189
                                                                     ------------
ADDITIONS:
   Income -
     Interest and dividend income                                       4,258,055
     Net appreciation in fair value of investments (Note 7)            27,699,119
                                                                     ------------
                     Net investment gain                               31,957,174
                                                                     ------------
   Contributions-
     Company, net of forfeitures                                        9,638,441
     Participant                                                       10,797,830
     Rollover                                                           1,532,212
                                                                     ------------
                     Total contributions                               21,968,483
                                                                     ------------

                     Total additions                                   53,925,657
                                                                     ------------
DEDUCTIONS:
   Benefits paid to participants                                        7,166,275
   Transfers to other plan, net (Note 4)                                  294,255
   Administrative expenses                                                 74,566
                                                                     ------------
                     Total deductions                                   7,535,096
                                                                     ------------

NET INCREASE IN NET ASSETS AVAILABLE FOR PLAN BENEFITS                 46,390,561
                                                                     ------------
NET ASSETS AVAILABLE FOR PLAN BENEFITS AT DECEMBER 31, 2003          $202,512,750
                                                                     ============


    The accompanying notes are an integral part of this financial statement.


                                       5

                               M-I RETIREMENT PLAN
                          NOTES TO FINANCIAL STATEMENTS

1.   SUMMARY OF SIGNIFICANT PLAN PROVISIONS

The following description of the M-I Retirement Plan (the "Plan") provides only
general information about the Plan's provisions in effect for the plan year
ended December 31, 2003. Participants should refer to the Plan document for a
more complete explanation of the Plan's provisions.

General and Eligibility

The Plan is a defined contribution plan of M-I SWACO (the "Company"). The
Company is a majority-owned subsidiary of Smith International, Inc. ("Smith").
The Plan is operated for the sole benefit of the employees of the Company and
their beneficiaries and is subject to the provisions of the Employee Retirement
Income Security Act of 1974, as amended ("ERISA"). The Plan is available to all
employees of the Company who meet certain eligibility requirements under the
Plan. Participation in the Plan may commence on the first day of the first month
following the date of hire. There is no minimum age requirement under the Plan.

Administration and Trustee

The Company is the plan administrator and sponsor of the Plan as defined under
ERISA. The Plan's operations are monitored by an administrative committee (the
"Administrative Committee") which is comprised of officers and employees of the
Company. Vanguard Fiduciary Trust Company ("Vanguard Trust" or the "Trustee") is
the trustee of all investments held by the Plan.

Contributions

The Plan allows participants to contribute a percentage of their compensation,
as defined by the Plan, subject to certain limitations of the Internal Revenue
Code of 1986, as amended (the "Code"). At its discretion, the Company may
provide contributions to the Plan for each participant equal to three percent of
the participant's compensation during the Plan year (the "Basic Contribution").
The Company may also provide matching contributions of up to 1.5 percent of a
participant's compensation (the "Matching Contribution"). For 2003, the Company
made a Basic Contribution equal to three percent of the participant's
compensation during the Plan year and a Matching Contribution equal to 100
percent of the first 1.5 percent of a participant's contribution. The Company's
Board of Directors may provide for an additional contribution (the
"Profit-Sharing Contribution") based on the financial performance of the Company
to eligible participants employed by the Company on December 31.

Vesting

Participants are fully vested in their contributions and related earnings and
vest in Company contributions and related earnings at the rate of 20 percent for
each year of service. Upon death, termination of employment by reason of total
or permanent disability or retirement from the Company upon reaching the normal
retirement age of 65, participants become fully vested in Company contributions
and related earnings.

The Plan has certain provisions that provide for service credit for vesting and
eligibility purposes for all employees who directly transfer employment between
Smith and the Company.

In connection with the purchase of business operations, the Company may elect to
amend the Plan to give past service credit to former employees of the acquired
operations who become employees of the Company.


                                       6

Investment Options

Participants have the option of investing their contributions and the Company's
Basic, Matching and Profit-Sharing Contributions among one or all of the seven
registered investment company funds, a common/collective trust offered by the
Vanguard Group of Investment Companies (the "Vanguard Funds") and the common
stock of Smith. Participants may transfer some or all of the balances out of any
fund into one or any combination of the other funds, including Smith common
stock, at any time.

Administrative Expenses

The Plan is responsible for its administrative expenses. The Company may elect
to pay administrative expenses from the forfeitures of the Plan or pay expenses
on behalf of the Plan.

Plan Termination

The Company intends for the Plan to be permanent; however, in the event of
termination, partial termination or discontinuance of contributions under the
Plan, the total balances of all participants shall become fully vested.

Loans

Participants may borrow from their accounts no more than once annually, subject
to terms specified by the Plan document. The Plan permits participants to borrow
the lesser of $50,000 or 50 percent of their vested account balances in the
Plan. These loans bear interest at prime and are repaid through payroll
withholdings over a period not to exceed five years, except for qualifying loans
to purchase a primary residence which may be repaid over an extended period.

Withdrawals and Forfeitures

A participant may elect to receive benefit payments through any one of the
several methods provided by the Plan upon termination or retirement. The Plan
also provides for hardship distributions to participants with immediate and
significant financial needs, subject to authorization by Plan management and
limited to the participant's vested account balance.

In the event that a participant terminates employment with the Company, the
participant's vested balances will be distributed at the participant's election
or distributed if the account balance is less than $5,000. Any unvested Company
contributions and related earnings/losses are forfeited if participants do not
return to the Company within 60 months of their termination. During 2003,
forfeitures of $427,627 and $74,566 were used to reduce the Company's
contributions and pay Plan expenses, respectively. Forfeitures available at
December 31, 2003 and 2002, totaled $30,330 and $20,607, respectively.

2.   SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Accounting

The accounts of the Plan are maintained on the cash basis of accounting. For
financial reporting purposes, however, the financial statements have been
prepared on the accrual basis of accounting.

Investment Valuation and Income Recognition

The Plan's investments are stated at fair value. Registered investment company
funds are valued at quoted market prices which represent the net asset value of
shares held by the Plan at year-end. The Smith stock fund is valued at its
year-end unit closing price (computed by dividing the sum of (i) the year-end
market price plus (ii) the uninvested cash position, by the total number of
member units). Participant loans are valued at cost which approximates fair
value.


                                       7

The Vanguard Retirement Savings Trust is a common/collective trust investing
primarily in guaranteed investment contracts ("GICS"). The GICS are fully
benefit responsive and are recorded at contract value. Contract value is
determined based on contributions made under the contract plus interest earned
at the contract's rate less funds used to pay investment fees and withdrawals.
There are no reserves against contract value for credit risk of the contract
issuer or otherwise. The effective yield of the collective trust fund was 4.25
percent for the year ended December 31, 2003. The average crediting interest
rate at December 31, 2003 was 4.42 percent.

Purchases and sales of Plan investments are recorded as of the trade date. The
net appreciation or depreciation in the fair value of investments reflected in
the accompanying statement of changes in net assets available for plan benefits
includes realized, as well as unrealized, gains or losses on the sale of
investments. The net change in realized gains and losses on sale are determined
using the actual purchase and sale price of the related investments. The net
changes in unrealized gains and losses are determined using the fair values as
of the beginning of the year or the purchase price if acquired since that date.

Participant Account Valuation

The Plan provides that net changes in unrealized appreciation and depreciation
and gains and losses upon sale are allocated daily to the individual
participant's account. The net changes, unrealized and realized, in a particular
investment fund are allocated in proportion to the respective participant's
account balance in each fund, after reducing the participant's account for
distributions, if any.

Dividend and interest income from investments is reported as earned on an
accrual basis in the statement of changes in net assets available for plan
benefits and is allocated to participants' accounts based upon each
participant's proportionate share of assets in each investment fund.

Use of Estimates

The preparation of financial statements in conformity with accounting principles
generally accepted in the United States of America requires the Administrative
Committee to make estimates and assumptions that affect the reported amounts of
assets and liabilities and changes therein, and disclosure of contingent assets
and liabilities.

3.  FEDERAL INCOME TAX STATUS

The Plan obtained its latest determination letter on January 21, 2003, in which
the Internal Revenue Service stated that the Plan, as then designed, was in
compliance with the applicable requirements of the Code. The Plan has been
amended for minor items since receiving the determination letter which, in the
opinion of the Administrative Committee, would not impact the status of the
Plan. Therefore, the Administrative Committee believes that the Plan is
qualified and the related trust was tax-exempt as of the financial statement
date.

4.  TRANSFERS TO OTHER PLAN

In conjunction with the direct transfer of certain employees between the Company
and Smith during 2003, net assets of $294,255 were transferred out of the Plan.


                                       8

5.   RISKS AND UNCERTAINTIES

The Plan provides for various investments in Smith common stock, registered
investment company funds and a common/collective trust. Investment securities,
in general, are exposed to various risks, such as interest rate, credit and
overall market volatility risk. Due to the level of risk associated with certain
investment securities, it is reasonably possible that changes in the values and
concentrations of investment securities will occur in the near term and those
changes could materially affect the amounts reported in the statement of net
assets available for Plan benefits. Historically, the investment mix has
remained relatively consistent. The allocation of total Plan assets by
investment type at December 31, is as follows:



                                                        2003           2002
                                                      -------        -------
                                                               
      Balanced Funds (Stocks and Bonds)                 35.9%          35.7%
      Domestic Stock Funds                              29.7           24.2
      Guaranteed investment contracts                   14.6           15.2
      Short-Term Investments                             6.5            9.9
      Smith International, Inc. common stock             5.3            6.3
      Participant loans                                  3.7            4.3
      Bond Funds                                         2.6            3.2
      International Stock Funds                          1.7            1.2
                                                      ------         ------
                                                       100.0%         100.0%
                                                      ======         ======



6.   RELATED-PARTY TRANSACTIONS

The Plan invests in shares of common stock of Smith. As Smith is the majority
owner of the sponsor, these transactions qualify as party-in-interest
transactions. In addition, the Plan invests in shares of registered investment
company funds and a common/collective trust fund managed by the Vanguard Group,
an affiliate of Vanguard Trust. As Vanguard Trust is the Trustee of the Plan,
these transactions qualify as party-in-interest transactions.

7.   INVESTMENTS

Individual investments, which exceed five percent of net assets available for
Plan benefits as of December 31, are as follows:



                                                         2003                 2002
                                                      -----------         -----------
                                                                    
      Vanguard Wellington Fund                        $71,310,917         $55,087,156
      Vanguard Retirement Savings Trust                29,018,978          23,462,279
      Vanguard PRIMECAP Fund                           28,231,946          16,427,023
      Vanguard Windsor Fund                            16,570,111          11,012,154
      Vanguard 500 Index Portfolio Fund                14,015,338           9,570,164
      Vanguard Prime Money Market Fund                 12,813,188          15,320,076
      Smith International, Inc. common stock           10,567,322           9,755,165


During 2003, the Plan's investments (including gains and losses on investments
bought and sold, as well as held during the year) appreciated in value as
follows:



                                                     2003
                                                  -----------
                                               
      Equity funds                                $14,305,971
      Smith International, Inc. common stock        3,173,224
      Balanced funds                               10,219,924
                                                  -----------
                                                  $27,699,119
                                                  ===========



                                        9

                               M-I RETIREMENT PLAN
                                 EIN: 76-0434986

                    FORM 5500, SCHEDULE H, PART IV, LINE 4i -
                    SCHEDULE OF ASSETS (HELD AT END OF YEAR)
                                DECEMBER 31, 2003




(a)              (b)                                        (c)                                (d)              (e)
                                             Description of Investment, Including
       Identity of Issue, Borrower,            Maturity Date, Rate of Interest,
         Lessor or Similar Party              Collateral, Par or Maturity Value                Cost         Current Value
       ----------------------------     ----------------------------------------------         ----         -------------
                                                                                                
*         Vanguard Group of
            Investment Companies        Vanguard Wellington Fund                                **          $ 71,310,917

*         Vanguard Group of
            Investment Companies        Vanguard Retirement Savings Trust                       **            29,018,978

*         Vanguard Group of
            Investment Companies        Vanguard PRIMECAP Fund                                  **            28,231,946

*         Vanguard Group of
            Investment Companies        Vanguard Windsor Fund                                   **            16,570,111

*         Vanguard Group of                                                                     **
            Investment Companies        Vanguard 500 Index Portfolio Fund                                     14,015,338

*         Vanguard Group of
            Investment Companies        Vanguard Prime Money Market Fund                        **            12,813,188

*         Smith International, Inc.     Smith International, Inc. common stock                  **            10,567,322

*         Vanguard Group of
            Investment Companies        Vanguard Long-Term Corporate Fund                       **             5,141,529

*         Vanguard Group of
            Investment companies        Vanguard International Growth Fund                      **             3,344,326

*         The Plan                      Participant loans (highest and lowest interest
                                          rates are 10.50% and 4.00%, respectively)             **             7,283,988
                                                                                                            ------------

                                           Total investments                                                $198,297,643
                                                                                                            ============


----------
*     Party-in-interest.

**    Cost information is not required for participant-directed investments and,
      therefore, is not included.


                                       10

                                   SIGNATURES

The Plan. Pursuant to the requirements of the Securities Exchange Act of 1934,
the trustees (or other persons who administer the employee benefit plan) have
duly caused this annual report to be signed on its behalf by the undersigned
hereunto duly authorized.

Dated: June 22, 2004                   M-I RETIREMENT PLAN


                                       By: Administrative Committee for the
                                       M-I Retirement Plan

                                       By: /s/ GERI D. WILDE
                                           -----------------
                                       Geri D. Wilde
                                       Assistant Treasurer


                                       11

                                  EXHIBIT INDEX


      Exhibit
      Number          Description
      ------          -----------
                   
       23.1           Consent of Independent Registered Public Accounting Firm



                                       12