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                                                                   Exhibit 10.1

                                    AGREEMENT


                  THIS AGREEMENT (this "Agreement") is effective as of the April
1, 2005 pending the closing of the merger (the "Separation Date"), between
Mittal Steel N.V. and International Steel Group Inc. (the "Company"), located at
4020 Kinross Lakes Parkway, Richfield, Ohio 44286 and LEONARD M. ANTHONY
("Executive"), residing at 7118 West Cross Creek Trail; Brecksville, Ohio 44141.

                                   WITNESSETH:

                  WHEREAS, prior to the Separation Date, Executive was the Chief
Financial Officer of the Company;

                  WHEREAS, effective on the Separation Date, Executive resigned
as an employee of the Company, and from any and all offices of the Company and
its subsidiaries, and any other position, office or directorship of any other
entity for which Executive was serving at the request of the Company; and

                  WHEREAS, the Company accepts Executive's resignation as of the
date referenced above; and

                  WHEREAS, the Company and Executive desire to set forth the
payments and benefits that Executive will be entitled to receive from the
Company in connection with his resignation from employment with the Company; and

                  WHEREAS, the Company and Executive wish to resolve, settle
and/or compromise certain matters, claims and issues between them, including,
without limitation, Executive's resignation from the offices he held and from
his employment with the Company.

                  NOW, THEREFORE, in consideration of the promises and
agreements contained herein and other good and valuable consideration, the
sufficiency and receipt of which are hereby acknowledged, and intending to be
legally bound, the Company and Executive hereby agree as follows:

         1. RESIGNATION. Executive hereby resigns, effective on the Separation
Date, his employment with the Company and its subsidiaries and related or
affiliated companies, and his position as Chief Financial Officer of the
Company. Executive further resigns, effective on the Separation Date, from any
other directorship, office, or position of the Company or any entity that is a
subsidiary of, or is otherwise related to or affiliated with, the Company (or to
which he has otherwise been appointed). The Company hereby consents to and
accepts said resignations.

         2. COMPENSATION AND BENEFITS. Subject to the conditions hereof, the
Company and Executive agree to the following:

                  A. SEVERANCE COMPENSATION. As severance compensation, the
Company shall pay Executive an amount equal to $1,865,000.00. Such amount shall
be paid to Executive in a lump sum payment, within ten (10) business days
following the Executive's execution of


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this Agreement and the expiration of the revocation period set forth in
Paragraph 4.c.(iv) hereof if Executive has not exercised his right of revocation
pursuant to such paragraph prior to such date. All of Executive's Stock Options
shall be cancelled as of the effective time of the merger with Mittal Steel
Company and Executive will receive in cash an amount equal to the difference
between $42.00 per share and the applicable per share exercise price of the
option.

                  B. MEDICAL COVERAGE. Executive shall be entitled to continue
to participate in the Company's medical, prescription drug, and dental plans or
programs in which he participated immediately prior to the Separation Date (with
a monthly premium cost to Executive equal to the premium cost as in effect for
active employees of the Company with respect to such plans or programs, as
amended or changed from time to time) until the earlier of (i) Executive's
coverage under another employer's or any other medical, prescription drug and/or
dental plans or programs or (ii) 24 months following the Separation Date (the
"Benefit Period"). The Company agrees that the period of coverage under such
plans shall not count against such plans' obligation to provide continuation
coverage pursuant to Part 6 of Subtitle B of Title I of the Employee Retirement
Income Security Act of 1974, as amended ("COBRA"). It is expressly understood
that the Company's payment obligations and Executive's participation rights
under this Paragraph 2.b. shall cease in the event Executive breaches any of the
agreements in Paragraph 3 hereof.

                  C. PROFESSIONAL FEES. The Company and Executive acknowledge
and agree that each shall be responsible for the payment of their respective
legal fees and costs (and related disbursements) incurred in connection with
Executive's resignation and all matters relating to the negotiation and
execution of the releases and all other matters covered by this Agreement;
provided however, that Executive shall be entitled to reimbursement of
reasonable attorney fees and expenses in connection with the enforcement of
Executive's rights under this agreement, provided that Executive is the
prevailing party in such a proceeding or dispute.

                  D. COMPANY BENEFIT PLANS. Except as provided above in
Paragraph 2.b. of this Agreement, Executive's post-Separation Date eligibility
for benefits, if any, as a past employee of the Company under the Company's
retirement and welfare benefit plans shall be as set forth in the respective
plan documents and shall be based on his employment termination on the
Separation Date, and his entitlement to benefits for the period of his
participation therein shall be determined pursuant to the terms thereof.

                  E. BUSINESS EXPENSES. The Company will reimburse Executive for
any reasonable business expenses incurred by Executive prior to the Separation
Date that are reimbursable pursuant to the Company's expense reimbursement
policies. All expense reimbursement requests must be presented to the Company
for payment not later than 30 days following the Separation Date.

                  F. ACCRUED SALARY. Executive shall be paid in accordance with
the Company's normal payroll cycle the gross amount of $14,583.33, less required
deductions, representing base salary through and including April 15, 2005; the
gross amount of $20,192.37, less required deductions, representing accrued but
unused 2005 vacation; and the gross amount of $262,500.00, less required
deductions, representing the amount earned under the Officers Cash and Stock
Bonus Plan as of the Separation Date.


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                  G. WITHHOLDING. The Company shall withhold such amounts from
the payments described herein as are required by applicable tax or other law.

         3. RESTRICTIVE COVENANTS. Executive will be bound by the following
restrictive covenants. If Executive fails to abide by any of the following
covenants, the Company may cease any remaining payments or benefits payable to
Executive hereunder.

                  A. For a period of 12 months after termination of the
Executive's employment with the Company, Executive shall not within the United
States, Canada and/or Mexico (i) engage, directly or indirectly, whether as an
employee, officer, director, consultant or otherwise, in the research,
development, manufacture, marketing, sale or distribution of steel or steel
products similar to those products sold or developed by the Company and/or any
Controlled Group member; (ii) solicit, directly, or indirectly, whether as an
employee, officer, director, consultant or otherwise, any person or entity which
is then a customer of the Company and/or any Controlled Group member or has been
a customer or solicited by the Company and/or any Controlled Group member for a
one (1) year period, to purchase steel or steel products from any entity other
than the Company and/or any Controlled Group member; (iii) solicit for
employment, engage and/or hire, whether directly or indirectly, any individual
who is then employed by the Company and/or any Controlled Group member; and/or
(iv) encourage or induce, whether directly or indirectly, any individual who is
then employed by the Company and/or any Controlled Group member to end his/her
business relationship with the Company and/or any Controlled Group member.

                  B. Executive will keep in strict confidence, and will not,
directly or indirectly, at any time during or after the Benefit Period,
disclose, furnish, disseminate, make available or, except in the course of
performing Executive's duties of employment, use any trade secrets or
confidential business and technical information of the Company or any Controlled
Group member or their customers or vendors, including without limitation as to
when or how Executive may have acquired such information. Such confidential
information shall include, without limitation, the Company's and any Controlled
Group member's unique selling, manufacturing and servicing methods and business
techniques, training, service and business manuals, promotional materials,
training courses and other training and instructional materials, vendor and
product information, customer and prospective customer lists, other customer and
prospective customer information and other business information. Executive
specifically acknowledges that all such confidential information, whether
reduced to writing, maintained on any form of electronic media, or maintained in
Executive's mind or memory and whether compiled by the Company, any Controlled
Group member and/or Executive, derives independent economic value from not being
readily known to or ascertainable by proper means by others who can obtain
economic value from its disclosure or use, that reasonable efforts have been
made by the Company and the Controlled Group members to maintain the secrecy of
such information, that such information is the sole property of the Company or
the Controlled Group members and that any retention and use of such information
by Executive during the Benefit Period shall constitute a misappropriation of
the Company's or any Controlled Group member's trade secrets.

                  C. For purposes of this Paragraph 3, "Controlled Group" shall
mean the Company and any other entity which is a member of the Company's
controlled group (as such term is defined in Sections 414(b) or 414(c) of the
Internal Revenue Code).


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         4. RELEASE BY EXECUTIVE.

                  A. Executive for himself and his dependents, successors,
assigns, heirs, executors and administrators (and his and their legal
representatives of every kind), hereby releases, dismisses, remisses and forever
discharges the Company from any and all arbitrations, claims (including claims
for attorney's fees), demands, damages, suits, proceedings, actions and/or
causes of action of any kind and every description, whether known or unknown,
which Executive now has or may have had for, upon, or by reason of any cause
whatsoever (except that this release shall not apply to (x) the obligations of
the Company arising under this Agreement and (y) Executive's rights of
indemnification by the Company, if any, pursuant to the Company's certificate of
incorporation or by-laws or any agreement between the Company and Executive),
against the Company ("claims"), including but not limited to:

                  (i) any and all claims, directly or indirectly, arising out of
         or relating to: (A) Executive's past employment or service with the
         Company; and (B) Executive's resignation as Chief Financial Officer of
         the Company and any other position described in Paragraph 1 of this
         Agreement.

                  (ii) any and all claims of discrimination, including but not
         limited to claims of discrimination on the basis of sex, race, age,
         national origin, marital status, religion or disability, including,
         specifically, but without limiting the generality of the foregoing, any
         claims under the Age Discrimination in Employment Act, as amended (the
         "ADEA"), Title VII of the Civil Rights Act of 1964, as amended, the
         Americans with Disabilities Act of 1990, the Family and Medical Leave
         Act of 1993 and Ohio Revised Code Chapter 4112;

                  (iii) any and all claims of wrongful or unjust discharge or
         breach of any contract or promise, express or implied; and

                  (iv) any and all claims under or relating to any and all
         employee compensation, employee benefit, employee severance or employee
         incentive bonus plans and arrangements, all of which Executive agrees
         are forfeited upon his resignation; provided that he shall remain
         entitled to the amounts and benefits described in Paragraph 2 above.
         Executive agrees that he intends to release any and all workers
         compensation claims he may have against the Company by this Agreement,
         and further agrees to execute any documentation as may be reasonably
         required to perfect such release when presented to him by the Company.

                  B. Executive understands and acknowledges that the Company
does not admit any violation of law, liability or invasion of any of his rights
and that any such violation, liability or invasion is expressly denied. The
consideration provided under this Agreement is made for the purpose of settling
and extinguishing all claims and rights (and every other similar or dissimilar
matter) that Executive ever had or now may have or ever will have against the
Company to the extent provided in this Paragraph 4. Executive further agrees and
acknowledges that no representations, promises or inducements have been made by
the Company other than as appear in this Agreement.


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                  C. Executive further understands and acknowledges that:

                  (i) The release provided for in this Paragraph 4, including
         claims under the ADEA to and including the date of this Agreement, is
         in exchange for the additional consideration provided for in this
         Agreement, to which consideration he was not heretofore entitled.

                  (ii) He has been advised by the Company to consult with legal
         counsel prior to executing this Agreement and the release provided for
         in this Paragraph 4, has had an opportunity to consult with and to be
         advised by legal counsel of his choice, fully understands the terms of
         this Agreement, and enters into this Agreement freely, voluntarily and
         intending to be bound;

                  (iii) He has been given a period of twenty-one days to review
         and consider the terms of this Agreement, and the release contained
         herein, prior to its execution and that he may use as much of the
         twenty-one day period as he desires; and

                  (iv) He may, within seven days after execution, revoke the
         release set forth in this Paragraph 4. Revocation shall be made by
         delivering a written notice of revocation to the Vice President of
         Human Resources at the Company. For such revocation to be effective,
         written notice must be actually received by the Vice President of Human
         Resources at the Company no later than the close of business on the
         seventh day after Executive executes this Agreement. If Executive does
         exercise his right to revoke this release, all of the terms and
         conditions of the Agreement shall be of no force and effect and the
         Company shall have no obligation to satisfy the terms or make any
         payment to Executive as set forth in Paragraph 2 of this Agreement.

                  D. Executive will never file a lawsuit or other complaint
asserting any claim that is released in this Paragraph 4.

                  E. Executive and the Company acknowledge that his resignation
is by mutual agreement between the Company and Executive, and that Executive
waives and releases any claim that he has or may have to reemployment.

                  F. For purposes of the above provisions of this Paragraph 4,
the "Company" shall include its present and former predecessors, subsidiaries,
divisions, related or affiliated companies, officers, directors, stockholders,
members, employees, heirs, successors, assigns, representatives, agents,
accountants and counsel.

         5. DISCLOSURE.

                  A. From the date of this Agreement through the end of the
Benefit Period, Executive will communicate the contents of Paragraphs 3, 6.b., 7
and 9 of this Agreement to any person, firm, association, or corporation other
than the Company which he intends to be employed by, associated in business
with, or represent.

                  B. Executive shall take no action with respect to the
Company's common stock that is in violation of the federal securities laws.


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         6. BREACH.

                  A. If Executive breaches any of the provisions of this
Agreement (and in the case of a breach that is capable of being cured, fails to
cure such breach within fifteen days after written notice by the Company to
Executive specifying the circumstances that constitute such breach), then the
Company may, at its sole option, immediately terminate all remaining benefits
described in this Agreement and obtain reimbursement from Executive of all
payments and benefits already provided pursuant to Paragraph 2 of this
Agreement, plus any expenses and damages incurred as a result of the breach
(including, without limitation, reasonable attorneys' fees), with the remainder
of this Agreement, and all promises and covenants herein, remaining in full
force and effect. Notwithstanding the foregoing, the Company will not terminate
pursuant to Paragraph 6.a. above any benefits to which Executive is entitled
under any tax-qualified retirement plan of the Company, and Executive's rights
under COBRA, if any, will not be reduced by any action taken by the Company
under Paragraph 6.a. above.

                  B. Executive acknowledges and agrees that the remedy at law
available to the Company for breach by Executive of any of his obligations under
Paragraphs 3 and 5 of this Agreement would be inadequate and that damages
flowing from such a breach would not readily be susceptible to being measured in
monetary terms. Accordingly, Executive acknowledges, consents and agrees that,
in addition to any other rights or remedies which the Company may have at law,
in equity or under this Agreement, upon adequate proof of Executive's violation
of any provision of Paragraphs 3 or 5 of this Agreement, the Company shall be
entitled to immediate injunctive relief and may obtain a temporary order
restraining any threatened or further breach, without the necessity of proof of
actual damage.

         7. CONTINUED AVAILABILITY AND COOPERATION.

                  A. Executive shall cooperate fully with the Company, the
Company's counsel and the Company's insurer in connection with any present and
future actual or threatened litigation or administrative proceeding involving
the Company that relates to events, occurrences or conduct occurring (or claimed
to have occurred) during the period of Executive's employment by the Company.
This cooperation by Executive shall include, but not be limited to:

                  (i) making himself reasonably available for interviews and
         discussions with the Company's counsel as well as for depositions and
         trial testimony;

                  (ii) if depositions or trial testimony are to occur, making
         himself reasonably available and cooperating in the preparation
         therefor as and to the extent that the Company or the Company's counsel
         reasonably requests;

                  (iii) refraining from impeding in any way the Company's
         prosecution or defense of such litigation or administrative proceeding;
         and

                  (iv) cooperating fully in the development and presentation of
         the Company's prosecution or defense of such litigation or
         administrative proceeding.

                  B. Executive shall be reimbursed by the Company for reasonable
travel, lodging, telephone and similar expenses incurred in connection with such
cooperation, which the


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Company shall reasonably endeavor to schedule at times not conflicting with the
reasonable requirements of any employer of Executive, or with the requirements
of any third party with whom Executive has a business relationship permitted
hereunder that provides remuneration to Executive. Executive shall not
unreasonably withhold his availability for such cooperation.

         8. SUCCESSORS AND BINDING AGREEMENT.

                  A. This Agreement shall be binding upon and inure to the
benefit of the Company and any successor of or to the Company, including,
without limitation, any persons acquiring, directly or indirectly, all or
substantially all of the business and/or assets of the Company whether by
purchase, merger, consolidation, reorganization, or otherwise (and such
successor shall thereafter be deemed included in the definition of "the Company"
for purposes of this Agreement), but shall not otherwise be assignable or
delegable by the Company.

                  B. This Agreement shall inure to the benefit of and be
enforceable by Executive's personal or legal representatives, executors,
administrators, successors, heirs, distributees, and/or legatees.

                  C. This Agreement is personal in nature and none of the
parties hereto shall, without the consent of the other parties, assign, transfer
or delegate this Agreement or any rights or obligations hereunder except as
expressly provided in Subparagraphs (a) and (b) of this Paragraph 8.

                  D. This Agreement is intended to be for the exclusive benefit
of the parties hereto, and except as provided in Subparagraphs (a) and (b) of
this Paragraph 8, no third party shall have any rights hereunder.

         9. NON-DISCLOSURE; STATEMENTS TO THIRD PARTIES.

                  A. Except as otherwise provided in Paragraph 5, all provisions
of this Agreement and the circumstances giving rise hereto are and shall remain
confidential and shall not be disclosed to any person not a party hereto (other
than (i) Executive's spouse, if any and (ii) each party's attorney, financial
advisor and/or tax advisor to the extent necessary for such advisor to render
appropriate legal, financial and tax advice), except as necessary to carry out
the provisions of this Agreement, and except as may be required by law.
Notwithstanding the foregoing, this Agreement may be disclosed and described as
well as filed with or provided to the Securities and Exchange Commission or any
other governmental instrumentality or agency, including the Internal Revenue
Service, if the Company deems such filing or provision to be necessary.

                  B. Because the purpose of this Agreement is to settle amicably
any and all potential disputes or claims among the parties, neither Executive
nor the Company shall, directly or indirectly, make or cause to be made any
statements to any third parties criticizing or disparaging the other or
commenting on the character or business reputation of the other. Executive
further hereby agrees not: (i) to comment to others concerning the status, plans
or prospects of the business of the Company, or (ii) to engage in any act or
omission that would be detrimental, financially or otherwise, to the Company, or
that would subject the Company to public disrespect, scandal, or ridicule. For
purposes of this Subparagraph 9.b., the "Company"


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shall mean the Company and its directors, officers, predecessors, parents,
subsidiaries, divisions, and related or affiliated companies, officers,
directors, stockholders, members, employees, heirs, successors, assigns,
representatives, agents, accountants and counsel.

         10. NOTICES. For all purposes of this Agreement, all communications
provided for herein shall be in writing and shall be deemed to have been duly
given when delivered, addressed to the Company (to the attention of Karen A.
Smith, Vice President Human Resources) at its principal executive offices and to
Executive at his principal residence, 7544 South Mannheim Court, Hudson, Ohio
44236, or to such other address as any party may have furnished to the other in
writing and in accordance herewith. Notices of change of address shall be
effective only upon receipt.

         11. MISCELLANEOUS. No provision of this Agreement may be modified,
waived or discharged unless such modification, waiver or discharge is agreed to
in writing signed by Executive and the Company. No waiver by either party hereto
at any time of any breach by the other party hereto or compliance with any
condition or provision of this Agreement to be performed by such other party
shall be deemed a waiver of similar or dissimilar provisions or conditions at
the same or at any prior or subsequent time. No agreements or representations,
oral or otherwise, expressed or implied with respect to the subject matter
hereof have been made by any of the parties that are not set forth expressly in
this Agreement and every one of them (if, in fact, there have been any) is
hereby terminated without liability or any other legal effect whatsoever.

         12. ENTIRE AGREEMENT. This Agreement embodies the complete agreement
and understanding between the parties with respect to the subject matter hereof
and effective as of its date supersedes and preempts any prior understandings,
agreements or representations by or between the parties, written or oral
(including without limitation, the Executive Severance Pay Plan, any employment
agreement between Executive and the Company, whether written or oral) and the
Officer Cash and Stock Bonus Plan), which may have related to the subject matter
hereof in any way.

         13. GOVERNING LAW. Any dispute, controversy, or claim of whatever
nature arising out of or relating to this Agreement or breach thereof shall be
governed by and under the laws of the State of Ohio. The parties agree that any
and all disputes, controversies, or claims of whatever nature arising out of or
relating to this agreement or breach thereof shall be resolved by a court of
general jurisdiction in the State of Ohio, and the parties hereby consent to the
exclusive jurisdiction of such court in any action or proceeding arising under
or brought to challenge, enforce, or interpret any of the terms of this
Agreement.

         14. VALIDITY. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision of this Agreement, which shall nevertheless remain in full force and
effect.

         15. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
together shall constitute one and the same Agreement.


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         16. CAPTIONS AND PARAGRAPH HEADINGS. Captions and Paragraph headings
used herein are for convenience and are not part of this Agreement and shall not
be used in construing it.

         17. FURTHER ASSURANCES. Each party hereto shall execute such additional
documents, and do such additional things, as may reasonably be requested by the
other party to effectuate the purposes and provisions of this Agreement.


                         [SIGNATURES ON FOLLOWING PAGE]


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                  IN WITNESS WHEREOF, the parties have executed and delivered
this Agreement as of the date set forth below.

                                     INTERNATIONAL STEEL GROUP INC.



                                     By:  /s/ Karen A. Smith
                                         -------------------------------
                                     Name: KAREN A. SMITH
                                     Title: VICE PRESIDENT HUMAN RESOURCES


                                     Date:  4-11-05
                                           -----------------------------


                                      /s/ Leonard M. Anthony
                                     -----------------------------------
                                     LEONARD M. ANTHONY


                                     Date:  4-11-05
                                           -----------------------------



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