Exhibit (10)(xviii)

GREAT LAKES CHEMICAL CORPORATION        2005 INCENTIVE COMPENSATION PLANPERSONAL AND CONFIDENTIAL

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GREAT LAKES CHEMICAL CORPORATION        INCENTIVE COMPENSATION PLAN

Purpose and Objectives

The purpose of the Incentive Compensation Plan (Plan) is to contribute to the motivation of key employees in accomplishing the Company goals. The objectives of
the Plan are as follows:



Plan Definitions

Certain words or phases used in this plan document are defined as follows:



Eligibility

Participants include key positions that significantly influence the performance of the Company and/or Business Unit. Participants are identified by salary band
and recommended by the head of each Business Unit or Corporate function, subject to the approval of the Incentive Compensation Review Committee.

Administration

The Compensation and Incentive Committee (C&IC) of the Board has ultimate authority over the Plan, is responsible for approving the Plan and may alter any
provision of the Plan or terminate the

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Plan
at any time. The Compensation and Incentive Committee of the Board will directly administer the Plan with respect to all participants. Specific responsibilities of this Committee include:



The
Incentive Compensation Review Committee, consisting of the Chief Executive Officer and the Senior Vice President, Human Resources and Communications will make recommendations to the
C&IC and resolve questions regarding the interpretation of the Plan.

Target Award Levels

The target incentive awards for each eligible position (by category) are expressed as a percentage of base salary as follows:

|ELIGIBLE POSITION                                          |  | TARGET INCENTIVE AWARD
|---------------------------------------------------------- |  | ----------------------
|CEO                                                        |  | 85 - 100%             
|President, Executive Vice President, Senior Vice President |  | 45% - 75%             
|Vice Presidents, General Managers, Directors               |  | 25% - 40%             
|Key Employees                                              |  | 7.5% - 20%            

Payout Ranges

Payout ranges are based upon target incentive award and are expressed as a percentage of base salary as follows:

|                           |  | MINIMUM |   | TARGET |   | MAXIMUM   |  
|-------------------------- |  | ------- | - | ------ | - | --------- | -
|Corp or BU Op Income & FCF |  | 0       | % | 100    | % | Unlimited |  
|Individual MBO's           |  | 0       | % | 100    | % | 200       | %

As
an incentive to increase shareholder value, Operating Income & FCF achievements, based upon actual results, are uncapped. That portion of participants' total earned incentive
award in excess of 200% will be converted to Great Lakes Chemical Corporation Restricted Stock Units (RSU's) and presented to the ICP participant with a three year cliff vesting period.

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Determination of Awards

Awards will be determined as follows:

|PARTICIPANT
GROUP |  | CORPORATE
OP INC + FCF |   | BUSINESS UNIT
OP INC + FCF |   | INDIVIDUAL
MBO
COMPONENT |  
|----------------- |  | ---------------------- | - | -------------------------- | - | ------------------------ | -
|Corporate         |  | *50                    | % |                            |   | **50                     | %
|Business Unit     |  |                        |   | *50                        | % | **50                     | %

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Distribution of Incentive Compensation

Awards under the Plan are to be paid to a participant in cash as soon as financial performance is determined and individual performance can be assessed. Awards
will typically be paid by March 15th following the close of a Plan year.

A
participant must be actively employed by the company on the date the bonus is paid to receive an incentive award. Participants hired or promoted to an eligible position during the Plan
year may receive a pro-rated incentive award (based on salary earned in the Plan year while in the eligible position) if approved by the Incentive Compensation Review Committee.

In
the event a participant's employment is terminated prior to the end of the Plan year due to death, disability, or normal retirement, the participant or beneficiary may be entitled to
receive the award that would have been earned if participant's employment had continued to the end of the Plan year, subject to the approval of the Incentive Compensation Review Committee.

At
the sole discretion of the Incentive Compensation Review Committee, a participant may not receive an incentive award due to poor individual performance or misconduct and may be
declared ineligible under the ICP.

Distribution of Restricted Stock Units

A participant must be actively employed by the company on the date the restricted stock unit award vest to receive such award. Non-vested awards will
lapse upon termination of employment. In the event a participant's employment is terminated prior to the end of the vesting period due to death, disability, or normal retirement, the participant or
beneficiary may be entitled to receive the award that would have vested if employment had continued to the end of the vesting period. These provisions are subject to the approval of the Incentive
Compensation Review Committee.

General Provisions

Limitations on Vested Interest



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Participants
may be deleted from or added to the Plan each year at the sole discretion of the Company.

Employment Rights



Non-Assignment



Withholding



Discontinuance, Suspension or Amendment of the Plan



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