CONSTAR INTERNATIONAL INC. ANNUAL INCENTIVE PLAN (Effective as of January 1, 2009)

Exhibit 99.1

CONSTAR INTERNATIONAL INC.

ANNUAL INCENTIVE PLAN

(Effective as of January 1, 2009)

TABLE OF CONTENTS

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CONSTAR INTERNATIONAL INC.

ANNUAL INCENTIVE PLAN

ARTICLE I

PURPOSES AND EFFECTIVE DATE

1.1. Purposes . This is the Constar International Inc. Annual Incentive Plan (the “Plan”), effective as of January 1, 2009. The purposes of the Plan are to attract and retain highly-qualified executives. The Plan is an unfunded plan that is not intended to be (a) subject to Parts 2, 3 or 4 of Title I, Subtitle B of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”) or (b) qualified under section 401(a) of the Code. The Plan is intended to comply with Section 409A of the Internal Revenue Code of 1986, as amended, (the “Code”) and is to be construed in accordance with Code Section 409A and the regulations and guidance thereunder.

1.2. Effective Date . The Plan is effective as of January 1, 2009.

ARTICLE II

DEFINITIONS

As used herein, the following terms shall have the following meanings:

2.1. “ Account ” means the bookkeeping reserve account established and maintained for each Participant for purposes of determining the amount payable to the Participant pursuant to the Plan; each Account shall consist of a Deferral Sub-Account, a Matching Sub-Account and such other subaccounts as are necessary or desirable in the opinion of the Committee for the convenient administration of the Plan. The establishment of an Account shall not require segregation of any funds of the Company or any Participating Employer or provide any Participant with any rights to any assets of the Company or any Participating Employer, except as a general creditor thereof. A Participant shall have no right to receive payment of any amount credited to the Participant’s Account except as expressly provided under the Plan.

2.2. “ Approved Distribution Date ” means a date at least five years after a Participant’s Normal Distribution Date that has been approved by the Committee on which distribution of the applicable portion of a Participant’s Matching Sub-Account will be made in accordance with Section 9.3.

2.3. “ Award Opportunity ” means the various levels of incentive awards, which a Participant may earn under the Plan, as established by the Committee pursuant to Article IV.

2.4. “ Base Salary ” means the regular base salary earned by a Participant during the Plan Year prior to any salary reduction contributions made to any of the Company’s or any Participating Employer’s deferred compensation plans, except as otherwise determined by the Committee in its sole discretion.

2.5. “ Beneficiary ” means the person(s), trust(s) or other entities the Participant designates, in accordance with procedures established by the Committee, to receive any benefits

under the Plan after the death of the Participant. If the Participant has not designated a Beneficiary, or if no Beneficiary survives the Participant, the aggregate amount then credited to the Participant’s Account shall be paid in a single sum to the Participant’s estate.

2.6. “ Board ” means the Board of Directors of the Company or, if the Board so directs, the Committee acting on behalf of the Board in the exercise of any and all powers and duties of the Board pursuant to this Plan.

2.7. “ Bonus ” means the annual performance bonus payable by a Participating Employer to a Participant under the Plan, as determined by the Committee after the end of such Plan Year. To be eligible to receive a Bonus, a Participant must be employed by a Participating Employer as of January 1 of the Plan Year following the Plan Year during which such Bonus is earned.

2.8. “ Cause ” means (a) a Participant, in carrying out his duties for the Participating Employer, engages in gross misconduct or gross negligence resulting in a material adverse effect on the Participating Employer, (b) a Participant embezzles any amount of the Participating Employer’s assets, (c) a Participant is convicted (including a plea of guilty or nolo contendere) of a felony involving moral turpitude, (d) a Participant’s breach of any restrictive covenant agreed to with the Participating Employer, or (e) a Participant’s willful and material failure to follow the lawful instructions of the Board. For purposes of this Section 2.8, no act, or failure to act, on the Participant’s part shall be considered “willful” unless done, or omitted to be done, by him in bad faith and without reasonable belief that his action or omission was in the best interest of the Participating Employer. Any act or omission to act by the Participant in reliance upon an opinion of counsel to the Participating Employer shall not be deemed to be willful.

2.9. “ Change in Control ” means:

(a) the acquisition by an individual, entity or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Exchange Act), during any 12-month period ending on the date of the most recent acquisition by such individual, entity or group, of beneficial ownership (within the meaning of Rule 13 d-3 promulgated under the Exchange Act) of more than 30% of the total voting power of the voting securities of the Company entitled to vote generally in the election of directors (the “Voting Securities”); provided, however, that the following acquisitions shall not constitute a Change in Control: (a) any acquisition, directly or indirectly by or from the Company or any Subsidiary, or by any employee benefit plan (or related trust) sponsored or maintained by the Company or any Subsidiary, (b) any acquisition by any underwriter in connection with any firm commitment underwriting of securities to be issued by the Company, or (c) any acquisition by any corporation if, immediately following such acquisition, 70% or more of the then outstanding shares of common stock of such corporation and the combined voting power of the then outstanding voting securities of such corporation (entitled to vote generally in the election of directors), are beneficially owned, directly or indirectly, by all or substantially all of the individuals and entities who, immediately prior to such acquisition, were the beneficial owners of the then outstanding Stock of the Company and the Voting Securities in substantially the same proportions, respectively, as their ownership, immediately prior to such acquisition, of the Stock and Voting Securities; or

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(b) The occurrence, during any 12-month period, of a reorganization, merger or consolidation, other than a reorganization, merger or consolidation with respect to which all or substantially all of the individuals and entities who were the beneficial owners, immediately prior to such reorganization, merger or consolidation, of the Stock and Voting Securities beneficially own, directly or indirectly, immediately after such reorganization, merger or consolidation 70% or more of the then outstanding common stock and voting securities (entitled to vote generally in the election of directors) of the corporation resulting from such reorganization, merger or consolidation in substantially the same proportions as their respective ownership, immediately prior to such reorganization, merger or consolidation, of the Stock and Voting Securities; or

(c) The sale or other disposition, during any 12-month period ending on the date of the most recent sale or disposition, of assets of the Company that have a total gross fair market value equal to or more than 40% of the total gross fair market value of all of the assets of the Company immediately before such sale or disposition, other than to a subsidiary, wholly-owned, directly or indirectly, by the Company or to a holding company of which the Company is a direct or indirect wholly owned subsidiary prior to such transaction; or

(d) During any period of 12 consecutive months, the individuals at the beginning of any such period who constitute the Board and any new director (other than a director designated by a person or entity who has entered into an agreement with the Company or other person or entity to effect a transaction described in Sections 2.9(a), (b) or (c) above) whose election by the Board or nomination for election by the Company’s stockholders was approved by a vote of a majority of the directors then still in office who either were directors at the beginning of any such period or whose election or nomination for election was previously so approved, cease for any reason to constitute a majority of the Board.

2.10. “ Code ” means the Internal Revenue Code of 1986, as amended.

2.11. “ Committee ” means the Compensation Committee of the Board, provided that, with respect to awards intended to qualify as “performance-based compensation” under Section 162(m) of the Code, such committee shall consist of two (2) or more individuals who are “outside directors” within the meaning of Section 162(m) of the Code, as amended from time to time.

2.12. “ Company ” means Constar International Inc., a corporation organized under the laws of the State of Delaware, or any successor corporation.

2.13. “ Disability ” means the Employee is (a) unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment that can be expected to result in death or can be expected to last for a continuous period of not less than 12 months, or (b) by reason of any medically determinable physical or mental impairment that can be expected to result in death or can be expected to last for a continuous period of not less than 12 months, receiving income replacement benefits for a period of not less than three months under an accident and health plan of the applicable Participating Employer. Notwithstanding the foregoing, if the Participating Employer maintains an accident and health plan, only subparagraph (b) hereof shall apply in determining whether an Employee is considered disabled for the purposes of this Plan.

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2.14. “ Employee ” means an officer or other key employee of a Participating Employer including a director who is such an employee.

2.15. “ Employer ” means the Company and any other entity included with the Company in a controlled group of corporations or trades or businesses within the meaning of Section 414(b) or Section 414(c) of the Code, provided that, for purposes of Section 2.25 hereof, in applying Code Section 1563(a)(1), (2), and (3) for purposes of determining a controlled group of corporations under Code Section 414(b), the language “at least 50 percent” is used instead of “at least 80 percent” each place it appears in Code Section 1563(a)(1), (2), and (3), and in applying Treasury Regulation §1.414(c)-2 for purposes of determining trades or businesses (whether or not incorporated) that are under common control for purposes of Code Section 414(c), “at least 50 percent” is used instead of “at least 80 percent” each place it appears in Treasury Regulation §1.414(c)-2.

2.16. “ Exchange Act ” means the Securities Exchange Act of 1934, as amended.

2.17. “ Matching Contribution ” means amounts credited to a Participant’s Account pursuant to Section 6.2.

2.18. “ Normal Distribution Date ” means the third anniversary of the date on which an amount is credited to a Participant’s Matching Sub-Account under Section 6.2 and on which distribution of such amount (adjusted for earnings) will be made in accordance with Section 9.2.

2.19. “ Participant ” means an Employee who is participating in the Plan pursuant to Article III.

2.20. “ Participating Employer ” means the Company and any Subsidiary, unless such Subsidiary is excluded as a Participating Employer by the Board, and any organization into which a Participating Employer may be merged or consolidated or to which all or substantially all of its assets may be transferred.

2.21. “ Plan ” means the Constar International Inc. Annual Incentive Plan as set forth herein and as amended from time to time.

2.22. “ Plan Year ” means the calendar year.

2.23. “ Retirement ” means, with respect to any Participant, Separation from Service after attainment of an age regarded by the Participating Employer as the normal retirement age for its employees in general, based upon the Participating Employer’s general employment and related policies and practices.

2.24. “ Separation from Service ” means a Participant’s termination of employment with the Employer that meets the requirements of a “separation from service” as defined under Section 409A of the Code and the regulations and other guidance thereunder.

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2.25. “ Specified Employee ” means, for any 12-month period beginning on April 1 and ending on the following March 31, a Participant who, as of the preceding December 31, was (i) an officer of an Employer having annual compensation (as defined in Section 414(q)(4) of the Code) greater than $130,000 (as adjusted under Section 416(i)(1) of the Code), (ii) a “five-percent owner” of an Employer (as defined in Section 416(i)(1)(B) of the Code), or (iii) a person having annual compensation (as defined in Section 414(q)(4) of the Code) of more than $150,000 and who would be classified as a “five-percent owner” of an Employer under Section 416(i)(1)(B) of the Code if “one percent” were substituted for “five percent” each time it appears in the definition of such term.

2.26. “ Stock ” means the common stock of the Company, par value $.01 per share, or such other class or kind of shares or other securities designated by the Committee.

2.27. “ Subsidiary ” means any corporation (other than the Company) in an unbroken chain of corporations beginning with the Company (or any subsequent parent of the Company) if each of the corporations other than the last corporation in the unbroken chain