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                                                            Exhibit No. (10)(xi)

                        GREAT LAKES CHEMICAL CORPORATION

                         1984 EMPLOYEE STOCK OPTION PLAN

                      As amended by the Board of Directors
                                       on
                                November 21, 1997

         1. Shares Subject to Option. 3,600,000 shares of common stock (after
adjustments for the 100 percent stock dividends in 1989 and 1991), par value
$1.00 per share, of the company (the "common stock") shall be reserved for
options granted under this Plan (the "Plan"). That number does not include
103,100 shares which are reserved for options granted under the company's 1975
Employee Stock Option Plan, as amended (the "1975 Plan"), and which are not
subject to presently outstanding options granted under the 1975 Plan. If any
option granted under this Plan shall terminate or expire without being fully
exercised for any reason prior to the end of the period under which options may
be granted under the Plan, the shares of common stock to which such termination
or expiration relates shall again become available for options thereafter
granted under this Plan.

         2. Effective Date and Duration of Plan. This Plan shall become
effective upon its approval by the holders of a majority of the common stock of
the Company present and voting (in person or by proxy) at the 1984 Annual
Meeting of Stockholders, and shall continue in effect for a period of ten (10)
years from the date of such stockholder approval. Upon expiration of such
10-year period, no further options shall be granted under this Plan (although
unexercised options theretofore granted under this Plan shall continue in
effect).

         3. Administration of the Plan. The Board of Directors (the "Board"),
which may act through its Compensation and Incentive Committee (previously the
Stock Option Committee) shall administer this Plan. It may in its sole
discretion determine the person or persons to whom options are to be granted and
the number of shares to be covered by each such option, all within the
limitations set forth in this Plan. It may interpret the provisions of the Plan
and decide all questions of fact arising in application of this Plan, and all
such interpretations and determinations shall be conclusive and binding upon the
individual employees involved and all persons claiming under them.

         4. Persons Eligible for Options. Only officers and other key employees
(including those who are also directors) of the company or any of its
subsidiaries may be granted options under this Plan. A person is a key employee
by virtue of meeting all of the following standards: (I) such person is employed
by the company or subsidiary, (ii) such person has managerial, supervisory
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 2

or professional, scientific, engineering or similar responsibilities, and (iii)
such person is not covered by any collective bargaining agreement binding on
such person's employer. No option shall be granted to any director of the
company or subsidiary who is not also an officer or key employee of the company
or one of its subsidiaries on the date the option is granted. For this purpose,
the term "subsidiary" shall mean any corporation in which the company owns stock
having 50 percent or more of the total combined voting power of all classes of
such corporation's stock.

         5. Terms and Conditions of Options. Options granted under this Plan may
be either Incentive Stock Options as defined in Section 422(a) of the Internal
Revenue Code of 1954, as amended (the "Code") (hereinafter referred to as
"ISOs") or options which are not within the Section 422(a) definition
(hereinafter referred to as "Nonstatutory Options") (ISOs and Nonstatutory
Options are hereinafter referred to collectively as "options").

         (a) Incentive Stock Options. The terms of each ISO granted under this
         Plan shall include those terms which are required by Section 422(a)of
         the Code and such other terms not inconsistent therewith as the Board
         may determine. The aggregate fair market value (determined as of the
         time of the granting of each option) of the shares of stock for which
         any officer or other key employee is granted such options (whether
         pursuant to this Plan or the 1975 Plan) in any calendar year shall not
         exceed the limitations provided by Section 422(a)(8) of the Code as the
         same may be amended from time to time, said limit at this time being
         $100,000 plus any unused limit carryover to such year (as defined in
         Section 422(a) of the Code).

         (b) Nonstatutory Options. Subject to the minimum option price specified
         in paragraph (c), the terms of each Nonstatutory Option granted under
         this Plan, which may be different in each case, shall be determined by
         the Board.

         (c) Minimum Option Price. The option price payable for the shares of
         stock subject to each ISO or Nonstatutory Option granted under this
         Plan shall not be less than the market value of the company's common
         stock on the date of the grant of such option. The fair market value of
         the company's stock at the time of grant of an option shall be deemed
         to be equal to the closing price on the preceding trading day on the
         American Stock Exchange or the New York Stock Exchange, as the case may
         be; provided, however, that during the [60]-day period from and after a
         change in control, "fair market value" shall mean, other than in the
         case of shares of common stock subject to ISOs, the higher of (X) the
         highest closing price on the American Stock Exchange or the New York
         Stock Exchange, as the case may
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 3

         be, during the 60-day period prior to the change in control and (Y) if
         the change in control is the result of a transaction or series of
         transactions described in paragraphs (a), (b) or (c) of Section
         12(A)(v) hereof, the highest price for shares of common stock paid in
         such transaction or series of transactions, which in the case of such
         paragraph (a) shall be the highest price for shares of common stock as
         reflected in a Schedule 13D filed under the Exchange Act (as defined in
         Section 12(A)(v)(a) hereof) by the person having made the acquisition.

        6. Cash Payments. Any one or more of the Nonstatutory Options granted
under this Plan may, in the discretion of the Board, provide that, upon the
exercise of such option, the optionee will receive a cash payment equal to the
excess of the market value (on the date of exercise) of the shares of the
company's common stock purchased upon exercise of the option over the option
price.

        7. Transfer Limitations. No option granted under this Plan shall be
transferable otherwise than by will or the laws of descent and distribution, and
no option granted under this Plan may be exercised by any person other than the
person to whom the option shall initially have been granted during the lifetime
of such initial optionee.

        8. Exercise of Options. Options shall be exercised by written notice to
the Company accompanied by payment in full of the option price and may be
exercised in one or more installments. Payment of the option price may be made
as specified in each Option Agreement (as discussed below), in cash (including
check, bank draft or money order), by exchanging common stock of the company
already owned by the optionee, or by delivery of a combination of cash and
common stock. The exchanged shares, plus cash, if any, must have a market value
on the date of exercise equal to the aggregate option price of the shares
acquired upon exercise of the option. The market value shall be considered to be
the closing price the preceding trading day on the American Stock Exchange or
the New York Stock Exchange, as the case may be. Notwithstanding the foregoing,
during the [60]-day period from and after a change in control, all optionees,
with respect to any or all of their respective options (including, in the case
of Nonstatutory Options, options already outstanding on [insert effective date
of amendment], 1997), shall, unless the Compensation and Incentive Committee
shall determine otherwise at the time of grant, have the right, in lieu of the
payment of the full option price of the shares of common stock being purchased
under the options and by giving written notice to the company in form
satisfactory to the Compensation and Incentive Committee, to elect (within such
[60]-day period) to surrender all or part of the options to the Company and to
receive in cash an amount equal to the amount by which the fair market value of
shares of common stock on the date of
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 4

exercise exceeds the option price per share of common stock under the options
multiplied by the number of shares of common stock granted under the options as
to which the right granted by this proviso shall have been exercised.

        9. Option Agreement. No person shall have any rights under this Plan
unless and until the company and the person to whom such option shall have been
granted shall have executed and delivered an agreement expressly granting the
option to such person and containing provision setting forth the terms of the
option.

        10. Anti-Dilution Provision. If, prior to the complete exercise of any
option, there shall be declared and paid a stock dividend upon the shares of
common stock of the Company or if the shares shall be split up, converted,
reclassified, changed into, or exchanged for, a different number or kind of
securities of the Company, the option, to the extent that it has not been
exercised, shall entitle the holder upon the future exercise of such option to
such number and kind of securities or other property subject to the terms of the
option to which the holder would be entitled had such holder actually owned the
shares subject to the unexercised portion of the option at the time of the
occurrence of such stock dividend, split-up, conversion, exchange,
reclassification or exchange; and the aggregate purchase price upon the future
exercise of the option shall be the same as if originally optioned shares were
being purchased thereunder. If any such event should occur, the number of shares
with respect to which options remain to be issued, or with respect to which
options may be reissued, shall be similarly adjusted.

         In the event the outstanding shares of common stock shall be changed
into or exchanged for any other class or series of capital stock or cash,
securities or other property pursuant to a recapitalization, reclassification,
merger, consolidation, combination or similar transaction (other than a
transaction described in the previous paragraph), then each option shall
thereafter become exercisable for the number and/or kind of capital stock,
and/or the amount of cash, securities or other property so distributed, into
which the shares subject to the option would have been changed or exchanged had
the option been exercised in full prior to such transaction, provided that, if
the kind or amount of capital stock or cash, securities or other property
received in such transaction is not the same for each outstanding share, then
the kind or amount of capital stock or cash, securities or other property for
which the option shall thereafter become exercisable shall be the kind and
amount so receivable per share by a plurality of the shares.

        11. Options Granted Under This Plan and 1975 Plan. Options which have
been or which may be granted under the 1975 Plan shall be governed by the
provisions of the 1975 Plan as amended. Options granted under this Plan shall be
governed by the provision of this Plan.
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 5

        12. Additional Provisions.

         A. VESTING, TERMINATION OF EMPLOYMENT.

                  (i) Upon a change in control of the Company (as defined
         below), all options shall immediately vest and become exercisable.

                  (ii) An option shall be exercisable only during the optionee's
         employment by the Company or a subsidiary and for up to three months
         after the termination of such employment for any reason (including but
         not limited to any such termination of employment which occurs
         following a change in control of the Company), except that in the
         Board's (or, if such authority is delegated by the Board, the
         Compensation and Incentive Committee's or the Chief Executive
         Officer's) discretion, an option may be exercisable for a period of up
         to three years after retirement or death, or for up to ten years after
         mandatory retirement under the Executive Mandatory Retirement Policy.

                  (iii) An option may be exercised after the termination of an
         optionee's employment with the Company only to the extent that (a) the
         optionee was entitled to do so on the date of termination (after giving
         effect to Section 12(A)(i) above), and (b) the Award would not have
         expired had the Awardee continued to be employed by the Company or a
         subsidiary.

                  (iv) The Board (or if such authority is delegated by the
         Board, the Compensation and Incentive Committee or the Chief Executive
         Officer) may in its discretion determine that an authorized leave of
         absence or disability shall be deemed to satisfy this Plan's employment
         requirements.

                  (v) For purposes of this Plan, a "change in control of the
         Company" shall be deemed to have occurred if the conditions set forth
         in any one of the following paragraphs shall have been satisfied:

                  (a)      any "person" (as such term is used in Section 13(d)
                           and 14(d) of the Securities Exchange Act of 1934, as
                           amended (the "Exchange Act")) other than (i) the
                           Company, (ii) a trustee or other fiduciary holding
                           securities under an employee benefit plan of the
                           Company, (iii) an underwriter temporarily holding
                           securities pursuant to an offering of such
                           securities, or
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 6

                           (iv) a corporation owned, directly or indirectly, by
                           the stockholders of the Company in substantially the
                           same proportions as their ownership of shares of the
                           Company (any such person is hereinafter referred to
                           as a "Person"), is or becomes the "beneficial owner"
                           (as defined in Rule 13d-3 under the Exchange Act),
                           directly or indirectly, of securities of the Company
                           representing more than 20% of the combined voting
                           power of the Company's then outstanding securities
                           (not including in the securities beneficially owned
                           by such Person any securities acquired directly from
                           the Company);

                  (b)      there is consummated a merger or consolidation of the
                           Company with or into any other corporation, other
                           than a merger or consolidation which would result in
                           the holders of the voting securities of the Company
                           outstanding immediately prior thereto holding
                           securities which represent, in combination with the
                           ownership of any trustee or other fiduciary holding
                           securities under an employee benefit plan of the
                           Company, immediately after such merger or
                           consolidation, more than 70% of the combined voting
                           power of the voting securities of either the Company
                           or the other entity which survives such merger or
                           consolidation or the parent of the entity which
                           survives such merger or consolidation;

                  (c)      the stockholders of the Company approve any plan or
                           proposal for the liquidation or dissolution of the
                           Company or an agreement for the sale or disposition
                           by the Company of all or substantially all the
                           Company's assets; or

                  (d)      during any period of two consecutive years (not
                           including any period prior to the date of this Plan),
                           individuals who at the beginning of such period
                           constitute the Board and any new director (other than
                           a director designated by a Person who has entered
                           into an agreement with the Company to effect a
                           transaction described in clause (a), (b) or (c) of
                           this paragraph) whose election by the Board or
                           nomination for election by the Company's stockholders
                           was approved by a vote of at least two-thirds (2/3)
                           of the directors then still in office who either were
                           directors at the beginning of the period or whose
                           election or nomination for election was previously so
                           approved, cease for any reason to constitute a
                           majority thereof.
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 7

                  For purposes of this Plan, where a change in control of the
                  Company results from a series of related transactions, the
                  change in control of the Company shall be deemed to have
                  occurred on the date of the consummation of the first such
                  transaction. For purposes of clause (a) of this subsection,
                  the stockholders of another corporation (other than the
                  Company or a corporation described in subclause (iv) of clause
                  (a) of this subsection) shall be deemed to constitute a
                  Person. Further, the sale, transfer, or other disposition of a
                  subsidiary of the Company shall not constitute a change in
                  control of the Company giving rise to payments or benefits
                  under this Plan.

                  Notwithstanding any other provision hereof, a "change in
                  control of the Company" shall not be deemed to have occurred
                  by virtue of the Company entering into any agreement with
                  respect to, the public announcement of, the approval by the
                  Company's stockholders or directors of, or the consummation
                  of, any transaction or series of integrated transactions
                  (including any merger or other business combination
                  transaction) entered into in connection with, or expressly
                  conditioned upon the occurrence of, a spin-off (such
                  transaction or series of integrated transactions, the
                  "Spin-Off Transaction") immediately following which the
                  recordholders of the common stock of the Company immediately
                  prior to the Spin-Off Transaction continue to have
                  substantially the same proportionate ownership in the spun-off
                  entity as they had in the Company immediately prior to the
                  Spin-Off Transaction; provided that such Spin-Off Transaction
                  (including any related merger of other business combination
                  transaction) has been approved by a vote of a majority of the
                  Company's Continuing Directors (as defined below) then in
                  office. For purposes of this Plan, a "Continuing Director"
                  shall mean any member of the Board of the Company who is a
                  member of the Board as of the date of this Plan and any person
                  who subsequently becomes a member of the Board, if such
                  person's nomination for election or election to the Board is
                  recommended or approved by a majority of the Continuing
                  Directors.

        B. Listings, Registration and Compliance With Laws and Regulations.

               (i) Each option shall be subject to the requirement that if at
        any time the Board shall determine, in its discretion, that the listing,
        registration, or qualification of the shares subject to the option upon
        any securities exchange or under any state or federal securities or
        other law or regulation, or the consent or approval of any governmental
        regulatory body, is necessary or desirable as a condition to or in
        connection with the granting of such
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 8

         option or the issue or purchase of shares thereunder, no such option
         may be exercised or paid in common stock in whole or in part unless
         such listing, registration, qualification, consent or approval shall
         have been effected or obtained free of any conditions not acceptable to
         the Board and the optionee will supply the company with such
         certificates, representations and information as the company shall
         request and shall otherwise cooperate with the company in obtaining
         such listing, registration, qualification, consent or approval. In the
         case of officers and other persons subject to Section 16(b) of the
         Securities Exchange Act of 1934, the Board may at any time impose any
         limitations upon the exercise of an option which, in the Board's
         discretion are necessary or desirable in order to comply with Section
         16(b) and the rules and regulations thereunder. If the company, as part
         of an offering of securities or otherwise, finds it desirable because
         of federal or state regulatory requirements to reduce the period during
         which any options may be exercised, the Board may, in its discretion
         and without the optionee's consent, so reduce such period on not less
         than 15 days' written notice to the optionee.

               (ii) Notwithstanding the terms of this paragraph, no optionee
           shall have the right to require the company to register, list or
           qualify said option or any of the stock underlying such option.

           C. Amendment of the Plan. Except as provided in the following
sentence and as required by law, the company's Board shall have complete power
and authority to amend this Plan at any time and no approval by the company's
stockholders or by any other person, committee or other entity of any kind shall
be required to make any such amendment effective. The Board shall not, however,
increase the maximum number of shares available for options granted under this
Plan unless such increase shall either be approved by the company's stockholders
or shall be permitted by Paragraph 10. No termination or amendment of this Plan
may, without the consent of the individual to whom any option shall theretofore
have been granted under this Plan, adversely affect the rights of such
individual under such option.

           D. Captions. The captions (i.e., all italicized words) used in this
Plan are for convenience only, do not constitute a part of this Plan, and shall
not be deemed to limit, characterize or affect in any way any provision of this
Plan, and all provisions in this Plan shall be construed as if no captions had
been used in this Plan.

           E. Severability. Whenever possible, each provision in this Plan and
in every option at any time granted under this Plan shall be interpreted in such
manner as to be effective and valid under applicable law, but if any provision
of this Plan or any option at any time granted under
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GREAT LAKES CHEMICAL CORPORATION
1984 EMPLOYEE STOCK OPTION PLAN
As amended on February 10, 1997
Page 9

this Plan shall be held to be prohibited by or invalid under applicable law,
then (I) such provision shall be deemed amended to accomplish the objectives of
the provision as originally written to the fullest extent permitted by law and
(ii) all other provisions of this Plan and every option at any time granted
under this Plan shall remain full force and effect.

           F. No Strict Construction. No rule of strict construction shall be
applied against the company, the Board, or any other person in the
interpretation of any of the terms of this Plan, any option granted under this
Plan or any rule or procedure established by the Board.

           G. Applicable Law. Every option at any time granted under this Plan
shall be deemed to be a contract made under the laws of the State of Indiana.
For all purposes, both this Plan and every option granted under this Plan shall
be construed in accordance with and governed by the laws of the State of
Indiana.