Exhibit 99.1

		Plains Exploration & Production Company 700 Milam, Suite 3100, Houston, TX 77002 www.pxp.com

NEWS RELEASE

FOR IMMEDIATE RELEASE

PXP PROVIDES PRELIMINARY 2010 OPERATIONAL RESULTS: REPORTS

16% INCREASE IN TOTAL PROVED RESERVES AND

302% RESERVE REPLACEMENT RATIO

Houston, Texas, January 31, 2011 - Plains Exploration & Production Company (NYSE:PXP) (“PXP” or the “Company”) today reported preliminary 2010 operational results.

PROVED RESERVES & PRODUCTION

Year-end estimated proved reserves of 416.1 million BOE were 54% oil and 46% natural gas. Further, estimated proved reserves were 57% developed and 43% undeveloped. The estimated reserves are based on the twelve-month average West Texas Intermediate oil price of $79.43 per barrel and Henry Hub natural gas price of $4.38 per million British thermal units. A detailed breakdown of reserves and costs incurred for 2010 will be provided when PXP reports full-year results on February 24, 2011. The following table provides a summary reconciliation of the Company’s proved reserves.

PXP’s 2010 fourth-quarter daily sales volumes averaged approximately 93,000 BOE per day, a 3% increase over 2010 third-quarter average volumes and a 9% increase over first-quarter 2010 average daily volumes.

PXP’s 2010 full-year daily sales volumes averaged approximately 88,500 BOE per day, a 7% increase over full-year 2009.

OPERATIONAL UPDATE

DEPRECIATION, DEPLETION AND AMORTIZATION

Fourth-quarter depreciation, depletion and amortization (DD&A) is expected to be $18.00 per BOE. For the full-year 2010, DD&A is expected to be $16.52 per BOE which is within the 2010 full-year guidance range of $16.00 - $18.00 per BOE.

For the full-year 2011, PXP estimates DD&A expense to be $16.00 to $18.00 per BOE. The 2011 full-year financial and operational guidance is included at the end of this release.

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2010 EARNINGS CONFERENCE CALL

PXP is scheduled to release 2010 fourth-quarter and year-end results on Thursday, February 24, 2011 before the market opens and will host its quarterly conference call that same day at 8:00 a.m. Central time. Investors wishing to participate in the conference call may dial 1-800-567-9836 or1-973-935-8460. The conference call and replay ID is: 36795961.The replay can be accessed by dialing 1-800-642-1687 or 1-706-645-9291. A live webcast of the conference call and a slide presentation will be available in the Investor Information section of PXP’s website at www.pxp.com.

PXP is an independent oil and gas company primarily engaged in the activities of acquiring, developing, exploring and producing oil and gas in California, Texas, Louisiana and the Gulf of Mexico. PXP is headquartered in Houston, Texas.

ADDITIONAL INFORMATION & FORWARD-LOOKING STATEMENTS

This press release contains forward-looking information regarding PXP that is intended to be covered by the safe harbor “forward-looking statements” provided by the Private Securities Litigation Reform Act of 1995. All statements included in this press release that address activities, events or developments that PXP expects, believes or anticipates will or may occur in the future are forward-looking statement. These include statements regarding:

These statements are based on our current expectations and projections about future events and involve known and unknown risks, uncertainties, and other factors that may cause our actual results and performance to be materially different from any future results or performance expressed or implied by these forward-looking statements. Please refer to our filings with the SEC, including our Form 10-K, for a discussion of these risks.

References to quantities of oil or natural gas may include amounts that the Company believes will ultimately be produced, but that are not yet classified as “proved reserves” under SEC definitions.

All forward-looking statements in this report are made as of the date hereof, and you should not place undue reliance on these statements without also considering the risks and uncertainties associated with these statements and our business that are discussed in this report and our other filings with the SEC. Moreover, although we believe the expectations reflected in the forward-looking statements are based upon reasonable assumptions, we can give no assurance that we will attain these expectations or that any deviations will not be material. Except as required by law, we do not intend to update these forward-looking statements and information.

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Plains Exploration & Production Company

Full-Year 2011 Operating and Financial Guidance

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⁽¹⁾ Steam gas costs assume a base SoCal Border index price of $4.81 per MMBtu. The purchased volumes are anticipated to be 42,000 - 45,000 MMBtu per day.

⁽²⁾ Production and ad valorem taxes assume base index prices of $85.00 per barrel and $5.00 per MMBtu.

⁽³⁾ Based on current outstanding and projected awards and current stock price.

⁽⁴⁾ Includes capitalized interest and general and administrative expenses.

⁽⁵⁾ If the index price is less than the $80 per barrel floor, we receive the difference between the $80 per barrel floor and the index price up to a maximum of $20 per barrel less the option premium. If the index price is at or above $80 per barrel, we pay only the option premium.

⁽⁶⁾ If the index price is less than the $80 per barrel floor, we receive the difference between the $80 per barrel floor and the index price up to a maximum of $20 per barrel less the option premium. We pay the difference between the index price and $110 per barrel plus the option premium if the index price is greater than the $110 per barrel ceiling. If the index price is at or above $80 per barrel but at or below $110 per barrel, we pay only the option premium.

⁽⁷⁾ If the index price is less than the $4.00 per MMBtu floor, we receive the difference between the $4.00 per MMBtu floor and the index price up to a maximum of $1.00 per MMBtu. We pay the difference between the index price and $4.92 per MMBtu if the index price is greater than the $4.92 per MMBtu ceiling. If the index price is at or above $4.00 per MMBtu but at or below $4.92 per MMBtu, no cash settlement is required.

⁽⁸⁾ If the index price is less than the $4.30 per MMBtu floor, we receive the difference between the $4.30 per MMBtu floor and the index price up to a maximum of $1.30 per MMBtu less the option premium. If the index price is at or above $4.30 per MMBtu, we pay only the option premium.

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