Exhibit 99.1

FOR IMMEDIATE RELEASE

Plains All American Pipeline, L.P. Reports

Strong First-Quarter 2011 Results

(Houston — May 4, 2011) Plains All American Pipeline, L.P. (NYSE: PAA) today reported net income attributable to Plains of $182 million, or $0.90 per diluted limited partner unit, for the first quarter 2011 as compared to net income attributable to Plains for the first quarter 2010 of $151 million, or $0.80 per diluted limited partner unit. The Partnership reported earnings before interest, taxes, depreciation and amortization (“EBITDA”) of $326 million for the first quarter 2011, compared with reported EBITDA of $276 million for the first quarter 2010.

The Partnership’s reported results include the impact of items that affect comparability between reporting periods. The impact of these items is excluded from adjusted results, as detailed in the table below. Accordingly, the Partnership’s first-quarter 2011 adjusted net income attributable to Plains, adjusted net income per diluted limited partner unit and adjusted EBITDA were $202 million, $1.03 and $348 million, respectively, as compared to respective first quarter 2010 measures of $147 million, $0.77 and $272 million. (See the section of this release entitled “Non-GAAP Financial Measures” and the attached tables for discussion of EBITDA and other non-GAAP financial measures and reconciliations of such measures to the comparable GAAP measures.)

“PAA delivered strong financial results for the first quarter 2011,” stated Greg L. Armstrong, Chairman & CEO of Plains All American.  “These results represent solid contributions from our fee-based segments and excellent performance from our supply and logistics segment during volatile market conditions.  As a result of PAA’s first-quarter performance, our favorable outlook for the second quarter and our expectation of baseline performance throughout the remainder of the year, we have increased our full-year 2011 adjusted EBITDA guidance by $75 million to a mid-point of $1.3 billion.”

“We ended the first quarter with a strong balance sheet, solid credit metrics and approximately $2.2 billion of committed liquidity.  As a result, we are well positioned to complete our 2011 organic growth capital program and to actively pursue additional organic and acquisition-oriented growth.”

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The following table summarizes selected items that the Partnership believes impact comparability of financial results between reporting periods (amounts in millions, except per unit amounts):

(1)                           Equity compensation expense for the three months ended March 31, 2011 and 2010 excludes the portion of equity compensation expense represented by grants under our Long-term Incentive Plans (“LTIPs”) that, pursuant to the terms of the grant, will be settled in cash only and have no impact on diluted units.  The portion of the equity compensation expense attributable to the cash portion of the LTIPs is approximately $6 million and $5 million for the three months ended March 31, 2011 and 2010, respectively.

(2)                           Includes gains and losses related to our interest rate derivative activities, but excludes gains and losses that are related to revalued inventory.  The three-month periods ended March 31, 2011 and 2010 include losses of less than $1 million and gains of less than $1 million, respectively, related to our interest rate derivative activities, which are included in other expense, net and interest expense, but do not impact segment profit.

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The following tables present certain selected financial information by segment for the first quarter (amounts in millions):

(1)                           Includes intersegment amounts.

(2)                           Segment general and administrative expenses (G&A) reflect direct costs attributable to each segment and an allocation of other expenses to the segments based on the business activities that existed at that time.  The proportional allocations by segment require judgment by management and will continue to be based on the business activities that exist during each period. Includes significant acquisition-related expenses in the Facilities segment for the 2011 period.

(3)                           Equity compensation expense for the three months ended March 31, 2011 and 2010 excludes the portion of equity compensation expense represented by grants under our Long-term Incentive Plans (“LTIPs”) that, pursuant to the terms of the grant, will be settled in cash only and have no impact on diluted units.  The portion of the equity compensation expense attributable to the cash portion of the LTIPs is approximately $6 million and $5 million for the three months ended March 31, 2011 and 2010, respectively.

(4)                           Includes gains and losses related to our interest rate derivative activities, but excludes gains and losses that are related to revalued inventory.  The three-month periods ended March 31, 2011 and 2010 include losses of less than $1 million and gains of less than $1 million, respectively, related to our interest rate derivative activities, which are included in other expense, net and interest expense, but do not impact segment profit.

Adjusted segment profit for the Transportation segment for the first quarter 2011 increased 7% over comparable 2010 results, primarily benefitting from higher average pipeline volumes partially offset by higher field operating expenses.

Adjusted segment profit for the Facilities segment for the first quarter 2011 increased 43% over comparable 2010 results, primarily due to capacity increases from organic growth capital projects and the Southern Pines acquisition.

Adjusted segment profit for the Supply and Logistics segment for the first quarter 2011 increased 48% over comparable 2010 results due to a combination of higher lease gathering volumes and margins, the benefit of the Nexen acquisition and net gains on the sale of excess inventory, as well as favorable crude oil quality differentials and market structure. These items were partially offset by higher operating and general and administrative expenses.

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The Partnership’s basic weighted average units outstanding for the first quarter 2011 totaled 143 million (144 million diluted) as compared to 136 million (137 million diluted) in last year’s first quarter. On March 31, 2011, the Partnership had approximately 149 million units outstanding, long-term debt of approximately $5.0 billion ($500 million of which supports hedged inventory) and an adjusted long-term debt-to-total capitalization ratio of 45%.

The Partnership has declared a quarterly distribution of $0.97 per unit ($3.88 per unit on an annualized basis) payable May 13, 2011 on its outstanding limited partner units. This distribution represents an increase of approximately 3.7% over the quarterly distribution paid in May 2010 and an increase of approximately 1.3% from the quarterly distribution paid in February 2011.

The Partnership will hold a conference call at 11:00 AM (Eastern) on Thursday, May 5, 2011 (see link below for details).  Prior to this conference call, the Partnership will furnish a current report on Form 8-K, which will include material in this press release and financial and operational guidance for the second quarter and full year of 2011. A copy of the Form 8-K will be available on the Partnership’s website at www.paalp.com.

Non-GAAP Financial Measures

To supplement our financial information presented in accordance with GAAP, management uses additional measures that are known as “non-GAAP financial measures” in its evaluation of past performance and prospects for the future. These measures include adjusted EBITDA and implied distributable cash flow (“DCF”).

Management believes that the presentation of such additional financial measures provides useful information to investors regarding our performance and results of operations because these measures, when used in conjunction with related GAAP financial measures, (i) provide additional information about our core operating performance and ability to generate and distribute cash flow, (ii) provide investors with the financial analytical framework upon which management bases financial, operational, compensation and planning decisions and (iii) present measurements that investors, rating agencies and debt holders have indicated are useful in assessing us and our results of operations.  These measures may exclude, for example, (i) charges for obligations that are expected to be settled with the issuance of equity instruments, (ii) the mark-to-market of derivative instruments that are related to underlying activities in another period (or the reversal of such adjustments from a prior period), (iii) items that are not indicative of our core operating results and business outlook and/or (iv) other items that we believe should be excluded in understanding our core operating performance. We have defined all such items as “Selected Items Impacting Comparability.” These additional financial measures are reconciled from the most directly comparable measures as reported in accordance within GAAP, and should be viewed in addition to, and not in lieu of, our consolidated financial statements and footnotes.

Although we present selected items that we consider in evaluating our performance, you should also be aware that the items presented do not represent all items that affect comparability between the periods presented. Variations in our operating results are also caused by changes in volumes, prices, exchange rates, mechanical interruptions, acquisitions and numerous other factors. These types of variations are not separately identified in this release, but will be discussed, as applicable, in management’s discussion and analysis of operating results in our Quarterly Report on Form 10-Q.

A reconciliation of EBITDA to net income and EBITDA to cash flows from operating activities for the periods presented are included in the tables attached to this release. In addition, the Partnership maintains on its website (www.paalp.com) a reconciliation of all non-GAAP financial information, such as EBITDA, to the most comparable GAAP measures. To access the information, investors should click on the “Investor Relations” link on the Partnership’s home page and then the “Non-GAAP Reconciliation” link on the Investor Relations page.

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Forward-Looking Statements

Except for the historical information contained herein, the matters discussed in this release are forward-looking statements that involve certain risks and uncertainties that could cause actual results to differ materially from results anticipated in the forward-looking statements. These risks and uncertainties include, among other things, failure to implement or capitalize on planned internal growth projects; maintenance of our credit rating and ability to receive open credit from our suppliers and trade counterparties; continued creditworthiness of, and performance by, our counterparties, including financial institutions and trading companies with which we do business; the effectiveness of our risk management activities; environmental liabilities or events that are not covered by an indemnity, insurance or existing reserves; abrupt or severe declines or interruptions in outer continental shelf production located offshore California and transported on our pipeline systems; shortages or cost increases of supplies, materials or labor; the availability of adequate third-party production volumes for transportation and marketing in the areas in which we operate and other factors that could cause declines in volumes shipped on our pipelines by us and third-party shippers, such as declines in production from existing oil and gas reserves or failure to develop additional oil and gas reserves; fluctuations in refinery capacity in areas supplied by our mainlines and other factors affecting demand for various grades of crude oil, refined products and natural gas and resulting changes in pricing conditions or transportation throughput requirements; the availability of, and our ability to consummate, acquisition or combination opportunities; our ability to obtain debt or equity financing on satisfactory terms to fund additional acquisitions, expansion projects, working capital requirements and the repayment or refinancing of indebtedness; the successful integration and future performance of acquired assets or businesses and the risks associated with operating in lines of business that are distinct and separate from our historical operations; unanticipated changes in crude oil market structure, grade differentials and volatility (or lack thereof); the impact of current and future laws, rulings, governmental regulations, accounting standards and statements and related interpretations; the effects of competition; interruptions in service on third-party pipelines; increased costs or lack of availability of insurance; fluctuations in the debt and equity markets, including the price of our units at the time of vesting under our long-term incentive plans; the currency exchange rate of the Canadian dollar; weather interference with business operations or project construction; risks related to the development and operation of natural gas storage facilities; future developments and circumstances at the time distributions are declared; general economic, market or business conditions and the amplification of other risks caused by volatile financial markets, capital constraints and pervasive liquidity concerns; and other factors and uncertainties inherent in the transportation, storage, terminalling and marketing of crude oil, refined products and liquefied petroleum gas and other natural gas related petroleum products discussed in the Partnership’s filings with the Securities and Exchange Commission.

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333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 800-564-3036

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Conference Call

The Partnership will host a conference call at 11:00 AM (Eastern) on Thursday, May 5, 2011 to discuss the following items:

1.               The Partnership’s first-quarter 2011 performance;

2.               The status of major expansion projects;

3.               Capitalization and liquidity;

4.               Financial and operating guidance for the second quarter and full year 2011; and

5.               The Partnership’s outlook for the future.

Webcast Instructions

To access the internet webcast, please go to the Partnership’s website at www.paalp.com, choose “Investor Relations,” and then choose “Conference Calls.”  Following the live webcast, the call will be archived for a period of sixty (60) days on the Partnership’s website.

If you are unable to participate in the webcast, you may access the live conference call by dialing toll free 800-230-1074. International callers should dial 612-234-9959. No password is required. You may access the slide presentation accompanying the conference call a few minutes prior to the call under the Conference Call Summaries portion of the Conference Calls tab of the Investor Relations section of PAA’s website at www.paalp.com.

Telephonic Replay Instructions

To listen to a telephonic replay of the conference call, please dial 800-475-6701, or, for international callers, 320-365-3844, and replay access code 197119.  The replay will be available beginning Thursday, May 5, 2011, at approximately 1:00 PM (Eastern) and continue until 12:59 PM (Eastern) Thursday, June 2, 2011.

Plains All American Pipeline, L.P. is a publicly traded master limited partnership engaged in the transportation, storage, terminalling and marketing of crude oil, refined products and liquefied petroleum gas and other natural gas related petroleum products. Through its general partner interest and majority equity ownership position in PAA Natural Gas Storage, L.P. (NYSE: PNG), PAA is also engaged in the development and operation of natural gas storage facilities. PAA is headquartered in Houston, Texas.

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS

(In millions, except per unit data)

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

OPERATING DATA (1)

(1)                           Volumes associated with acquisitions represent total volumes for the number of days or months (dependent on the calculation) we actually owned the assets divided by the number of days or months in the period.

(2)                           The aggregate of multiple systems in the respective areas.

(3)                           Facilities total is calculated as the sum of: (i) crude oil, refined products and LPG storage capacity; (ii) natural gas capacity divided by 6 to account for the 6:1 mcf of gas to crude Btu equivalent ratio and further divided by 1,000 to convert to monthly volumes in millions; and (iii) LPG processing volumes multiplied by the number of days in the period and divided by the number of months in the period.

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEET DATA

(In millions)

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

CREDIT RATIOS

(In millions)

(1)                           The adjustment represents the portion of the $500 million, 4.25% senior notes due September 2012 that has been used to fund hedged inventory and would be classified as short-term debt if funded on our credit facilities.  These notes were issued in July 2009 and the proceeds are being used to supplement capital available from our hedged inventory facility.

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

COMPUTATION OF BASIC AND DILUTED EARNINGS PER LIMITED PARTNER UNIT

(In millions, except per unit data)

(1)                           We calculate net income available to limited partners based on the distribution paid during the current quarter (including the incentive distribution interest in excess of the 2% general partner interest).  However, FASB guidance requires that the distribution pertaining to the current period’s net income, which is to be paid in the subsequent quarter, be utilized in the earnings per unit calculation.  After adjusting for this distribution, the remaining undistributed earnings or excess distributions over earnings, if any, are allocated to the general partner and limited partners in accordance with the contractual terms of the partnership agreement for earnings per unit calculation purposes.  We reflect the impact of the difference in (i) the distribution utilized and (ii) the calculation of the excess 2% general partner interest as the “Adjustment in accordance with application of the two-class method for MLPs.”

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

FINANCIAL DATA RECONCILIATIONS

(In millions)

(1)                           Includes distributions that pertain to the current quarter’s net income and are to be paid in the subsequent quarter.

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

FINANCIAL DATA RECONCILIATIONS

(In millions, except per unit data) (continued)

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333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 800-564-3036