Exhibit 99.1

News from Aon

Aon Reports Fourth Quarter and Full Year 2011 Results

- Total revenue increased 3% to $3.0 billion with organic revenue growth of 3% -

- EPS from continuing operations increased 22% to $0.82 -

Fourth Quarter Summary

·                  EPS from continuing operations, adjusted for certain items, increased 15% to $0.97

·                  Risk Solutions revenue increased 3% to $1.8 billion with organic revenue growth of 3%

·                  Risk Solutions operating margin was 18.9% and the operating margin, adjusted for certain items, decreased 10 basis points to 21.8%

·                  HR Solutions revenue increased 3% to $1.2 billion with organic revenue growth of 3%

·                  HR Solutions operating margin was 11.3% and the operating margin, adjusted for certain items, decreased 120 basis points to 12.4%

·                  Subsequent to the close of the fourth quarter, the Company announced the intention to change its jurisdiction of incorporation from Delaware to the U.K., pending shareholder approval and satisfaction of other conditions

CHICAGO, IL — February 3, 2012 - Aon Corporation (NYSE: AON) today reported results for the fourth quarter and full year ended December 31, 2011.

Net income attributable to Aon stockholders from continuing operations increased 19% to $277 million or $0.82 per share, compared to $232 million or $0.67 per share for the prior year quarter.  Net income per share attributable to Aon stockholders from continuing operations, adjusted for certain items, increased 15% to $0.97, compared to $0.84 in the prior year quarter.  Certain items that impacted fourth quarter results and comparisons with the prior year quarter are detailed in the “Reconciliation of Non-GAAP Measures - Operating Income and Diluted Earnings per Share” on page 14 of this press release.

“Our fourth quarter results reflect 15 percent growth in earnings as highlighted by organic growth across all major businesses and the continued delivery of synergy savings related to Aon Hewitt,” said Greg Case, president and chief executive officer.  “While macro economic conditions remain challenging globally, we are firmly on track to deliver improved growth in 2012, our restructuring programs will deliver cost savings and we have solid financial flexibility that will drive increased shareholder value, as highlighted by the repurchase of $828 million of common stock in 2011.”

FOURTH QUARTER FINANCIAL SUMMARY

Total revenue increased 3% to $3.0 billion from the prior year quarter driven primarily by a 3% increase in organic revenue.

Total operating expenses increased 3%, or $72 million, to $2.6 billion due primarily to a 3% increase in organic revenue, a $21 million increase in intangible asset amortization expense and $18 million of non-cash charges related to the write-off of accounts receivable primarily from the years 2001 to 2004, partially offset by benefits related to the restructuring programs a $15 million unfavorable impact from foreign currency exchange rates, and a $14 million decline in restructuring costs.

Depreciation expense decreased 3%, or $2 million, to $56 million compared to the prior year quarter.

Intangible asset amortization expense increased 31%, or $21 million, to $89 million compared to the prior year quarter due primarily to a $22 million increase relating to assets recognized from the merger with Hewitt.

Restructuring expenses were $43 million compared to $57 million in the prior year quarter.  In the fourth quarter, the Company incurred $25 million of costs under the Aon Hewitt restructuring program and $21 million of costs under the Aon Benfield restructuring program primarily related to workforce reduction.  The Company has completed all restructuring activities and incurred 100% of the total costs for the 2007 restructuring program and has incurred approximately 96% of the total costs necessary to deliver the remaining $22 million of restructuring savings for the Aon Benfield restructuring program.  An analysis of restructuring-related costs is detailed on page 16 of this release.

Restructuring savings in the fourth quarter related to the 2007 restructuring program are estimated at $134 million compared to $128 million in the prior year quarter.  Of the restructuring savings in the fourth quarter, $113 million were related to the Risk Solutions segment.  Before any potential reinvestment of savings, the 2007 restructuring delivered cumulative expense savings of $536 million in 2011.

Restructuring savings in the fourth quarter related to the Aon Benfield restructuring program are estimated at $33 million compared to $27 million in the prior year quarter.  Before any potential reinvestment of savings, the Benfield restructuring program is expected to deliver cumulative expense savings of $144 million in 2012 related to the Risk Solutions segment.

Restructuring savings in the fourth quarter related to the Aon Hewitt restructuring program are estimated at $43 million compared to $4 million in the prior year quarter.  The Company expects to deliver cumulative expense savings of $355 million in 2013 related to the merger with Hewitt, including $280 million related to the restructuring program and $75 million in additional synergy savings from areas such as information technology, procurement and public company costs.  Associated with the transfer of the Health and Benefits business effective January 1, 2012, approximately $20 million of the estimated savings under the Aon Hewitt restructuring program will be achieved in the Risk Solutions segment.

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Currency fluctuations in the fourth quarter had a $0.01 favorable impact on adjusted net income from continuing operations per diluted share when the Company translates prior year quarter results at current quarter foreign exchange rates.

Effective tax rate on net income from continuing operations declined to 27.0% in the fourth quarter compared to 32.8% in the prior year quarter.  The prior year quarter was unfavorably impacted by certain deferred tax adjustments.  The Company anticipates an effective tax rate on net income from continuing operations of approximately 29.0% in 2012.

Average diluted shares outstanding decreased to 337.9 million in the fourth quarter compared to 346.7 million in the prior year quarter due primarily to the Company’s share repurchase program in 2011.  The Company did not repurchase shares during the fourth quarter due to the subsequent announcement of the relocation of the corporate headquarters.  The Company has approximately $1.2 billion of common stock remaining under the share repurchase program.

FOURTH QUARTER SEGMENT REVIEW

Certain noteworthy items impacted operating income and operating margins in the fourth quarter of 2011 and 2010.  The fourth quarter segment reviews provided below include supplemental information related to organic revenue, adjusted operating income and operating margin, which is described in detail on the “Reconciliation of Non-GAAP Measures - Organic Revenue” on page 13 and “Reconciliation of Non-GAAP Measures - Operating Income and Diluted Earnings per Share” on page 14 of this press release.

RISK SOLUTIONS

Risk Solutions total revenue increased 3% to $1.8 billion compared to the prior year quarter due primarily to 3% organic growth in commissions and fees.

Retail Brokerage organic revenue increased 2% reflecting revenue growth in both the Americas and International businesses.  Americas organic revenue increased 3% primarily as a result of strong management of the renewal book portfolio in Latin America and the U.S. and solid new business growth in both Canada and Latin America.  International organic revenue increased 1% driven by strong growth in Asia and emerging markets, partially offset by challenging macro-economic conditions in continental Europe.  Reinsurance organic revenue increased 4% due primarily to strong growth in capital market transactions and advisory business and modest growth in global facultative placements.

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Compensation and benefits for the fourth quarter increased 5%, or $48 million, compared to the prior year quarter due primarily to 3% organic revenue growth and a $30 million increase in restructuring costs, partially offset by benefits related to the restructuring programs.  Other expenses for the fourth quarter increased 9%, or $39 million, primarily due to $18 million of non-cash charges related to the write-off of accounts receivable primarily from the years 2001 to 2004, 3% organic revenue growth and $4 million of integration costs related to the recent acquisition of Glenrand M-I-B.

Fourth quarter operating income decreased 8% to $345 million.  Adjusting for certain items detailed on page 14 of this press release, operating income increased 3%, or $10 million compared to the prior year quarter, and operating margin decreased 10 basis points to 21.8% due primarily to a 20 basis point unfavorable impact for integration costs related to recent acquisitions.

HR SOLUTIONS

HR Solutions total revenue increased 3% to $1.2 billion compared to the prior year quarter due primarily to 3% organic growth in commissions and fees.

Organic revenue in Consulting Services increased 2% driven primarily by growth in health and benefits and investment management consulting, partially offset by a decline in retirement consulting.  Organic revenue in Outsourcing increased 4% due primarily to new client wins in HR business process outsourcing and health care exchanges, partially offset by price compression and client losses in benefits administration.

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Compensation and benefits for the fourth quarter decreased 6%, or $42 million, from the prior year quarter due primarily to benefits related to the Aon Hewitt restructuring program and a $39 million decline in restructuring costs, partially offset by 3% organic revenue growth and investment in the business.  Other expenses increased 8%, or $26 million, from the prior year quarter due primarily to a $22 million increase in intangible asset amortization expense and 3% organic revenue growth, partially offset by benefits related to the Aon Hewitt restructuring program.

Fourth quarter operating income increased 55% to $133 million.  Adjusting for certain items detailed on page 14 of this press release, operating income decreased 6%, or $10 million, to $147 million and operating margin decreased 120 basis points to 12.4% versus the prior year quarter due primarily to a 190 basis point impact from intangible asset amortization expense, investment in the business and an unfavorable revenue mix shift, partially offset by benefits related to the restructuring program.

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INCOME FROM CONTINUING OPERATIONS

Unallocated expenses increased $5 million to $43 million including costs for project-related work.   Interest income decreased $2 million to $4 million due to lower average interest rates.  Interest expense decreased $6 million to $59 million due primarily to a decline in the average rate on total debt outstanding.  Other income of $4 million in the fourth quarter includes gains on certain Company owned life insurance plans, partially offset by losses on the Company’s ownership in certain private equity securities and other long-term investments.  The prior year quarter included a loss of $8 million on extinguishment of debt and losses related to certain long-term investments, partially offset by gains related to the Company’s ownership in certain insurance investment funds.

2011 FULL YEAR SUMMARY

Total revenue for 2011 increased 33% to $11.3 billion due to a 29% increase in commissions and fees resulting from acquisitions, primarily Hewitt, net of dispositions, a 2% increase in organic revenue driven by Risk Solutions, and a 2% favorable impact from foreign currency exchange rates. Risk Solutions total revenue increased 6% to $6.8 billion and HR Solutions total revenue increased 113% to $4.5 billion as a result of the merger with Hewitt.

Net income attributable to Aon stockholders for 2011 increased 39% to $979 million compared to $706 million for the prior year.  Net income attributable to Aon stockholders from continuing operations increased 33% to $975 million compared to $733 million for the prior year.  Net income attributable to Aon stockholders, adjusted for certain items, increased 21% to $1.1 billion compared to $929 million for the prior year.  Certain items that impacted full year results and comparisons against the prior year are detailed in the “Reconciliation of Non-GAAP Measures - Operating Income and Diluted Earnings per Share” on page 14 of this press release.

Net income attributable to Aon stockholders for 2011 increased 21% to $2.87 per share compared to $2.37 per share for the prior year.  Net income attributable to Aon stockholders from continuing operations increased 16% to $2.86 per share compared to $2.46 per share for the prior year.  Net income attributable to Aon stockholders, adjusted for certain items, increased 5% to $3.29 per share compared to $3.12 per share for the prior year.  Certain items that impacted full year results and comparisons against the prior year are detailed in the “Reconciliation of Non-GAAP Measures - Operating Income and Diluted Earnings per Share” on page 14 of this press release.

During 2011, the Company repurchased approximately 16.4 million shares of common stock for $828 million at an average price of $50.39 per share.

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SUBSEQUENT ANNOUNCEMENT

On January 13, 2012, the Company announced, as an important part of its global growth strategy, it intends to change its jurisdiction of incorporation from Delaware to the U.K. and move its corporate headquarters to London.  The proposed transaction requires shareholder approval and is expected to close in the second quarter of 2012 subject to the satisfaction of other conditions.

CHANGES TO DISCLOSURE IN 2012

Effective January 1, 2012, the Company moved the global Aon Hewitt Health and Benefits businesses from the HR Solutions segment into the Risk Solutions segment.  This move will allow the businesses to benefit from a broader global distribution channel and to promote the Company’s deep health and benefits capabilities in data and analytics with clients and insurance carriers.

Effective January 1, 2012, the Company will begin reporting adjusted results that exclude the impact of non-cash intangible asset amortization and certain one-time items.

Historical selected financial information for the years 2009, 2010 and 2011, that fully reflect the disclosure changes for both the Health and Benefits transfer and for intangible amortization, are provided on pages 19-22 of this press release.

Conference Call, Presentation Slides and Webcast Details

The Company will host a conference call on Friday, February 3, 2012 at 7:30 a.m. central time.  Interested parties can listen to the conference call via a live audio webcast and view the presentation slides at www.aon.com.

About Aon

Aon Corporation (NYSE: AON) is the leading global provider of risk management, insurance and reinsurance brokerage, and human resources solutions and outsourcing services.  Through its more than 61,000 colleagues worldwide, Aon unites to empower results for clients in over 120 countries via innovative and effective risk and people solutions and through industry-leading global resources and technical expertise.  Aon has been named repeatedly as the world’s best broker, best insurance intermediary, reinsurance intermediary, captives manager and best employee benefits consulting firm by multiple industry sources.  Visit http://www.aon.com for more information on Aon.

Safe Harbor Statement

This communication contains certain statements related to future results, or states our intentions, beliefs and expectations or predictions for the future which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results depending on a variety of factors. Potential factors that could impact results include: the planned change in global headquarters and jurisdiction of incorporation (the “Reorganization”) may not be approved by Aon’s stockholders; changes in circumstances beyond Aon’s control, including changes in foreign or domestic laws, regulatory actions, orders or rulings by foreign or domestic governmental entities, Aon’s possible removal from the S&P 500 stock index and the possibility that the Class A Ordinary Shares of Aon’s U.K. successor will not be eligible for acceptance by DTC may

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effectively preclude Aon from completing the Reorganization or reduce or eliminate the benefits Aon expects to achieve from the Reorganization; the possibility that the expected efficiencies and cost savings from the merger with Hewitt Associates Inc. (“Hewitt”) will not be realized, or will not be realized within the expected time period; the risk that the Aon and Hewitt businesses will not be integrated successfully; general economic conditions in different countries in which Aon does business around the world; changes in global equity and fixed income markets that could affect the return on invested assets; fluctuations in exchange and interest rates that could influence revenue and expense; rating agency actions that could affect Aon’s ability to borrow funds; funding of Aon’s various pension plans; our ability to implement restructuring initiatives and other initiatives intended to yield cost savings, and the ability to achieve those cost savings; changes in the competitive environment; changes in commercial property and casualty markets and commercial premium rates that could impact revenues; continued compliance with settlement agreements related to compliance with the U.S. Foreign Corrupt Practices Act and non-U.S. anti-corruption laws; the impact of investigations brought by U.S. state attorneys general, U.S. state insurance regulators, U.S. federal prosecutors, U.S. federal regulators, and regulatory authorities in the U.K. and other countries; the impact of class actions and individual lawsuits including client class actions, securities class actions, derivative actions and ERISA class actions; the cost of resolution of other contingent liabilities and loss contingencies, including potential liabilities arising from error and omissions claims against Aon; the extent to which Aon retains existing clients and attracts new businesses; the extent to which Aon manages certain risks created in connection with the various services, including fiduciary and advisory services, among others, that Aon currently provides, or will provide in the future, to clients; the extent to which Aon retains existing employees and attracts new personnel, including potential difficulties in executive succession planning related to our need to attract talent to London if the reorganization is completed; Aon’s ability to maintain the security and privacy of confidential information belonging to its clients or their personnel; Aon’s ability to innovate and keep pace with rapid and continuing changes in technology, industry standards and client preferences; the impact of, and potential challenges in complying with, legislation and regulation in the jurisdictions in which Aon operates, particularly given the global scope of Aon’s  businesses and the possibility of conflicting regulatory requirements across jurisdictions in which Aon does business; changes in costs or assumptions associated with our outsourcing and consulting engagements that affect the profitability of these engagements; and the implementation of changes to the methods in which Aon internally process and monitors transactions. Further information concerning Aon and its business, including factors that potentially could materially affect Aon’s financial results, is contained in Aon’s and, historically, Hewitt’s filings with the SEC. See Aon’s Annual Report on Form 10-K and Annual Report to Stockholders for the fiscal year ended December 31, 2010 and Quarterly Reports on Form 10-Q for the subsequent fiscal quarters and other public filings with the SEC for a further discussion of these and other risks and uncertainties applicable to our businesses. Aon does not undertake, and expressly disclaims, any duty to update any forward-looking statement whether as a result of new information, future events or changes in their respective expectations, except as required by law.

Additional Information

This communication is being made in respect of a proposed corporate reorganization involving Aon Corporation (“Aon”), which will result in Aon’s stockholders holding Class A Ordinary Shares in a newly-formed public limited company organized under English law.  In connection with the proposed reorganization, Aon Global Limited, a subsidiary of Aon (which will become a public limited company) (“Aon UK”) has filed with the SEC a registration statement on Form S-4 that included a preliminary proxy statement/prospectus, and each of Aon and Aon UK may be filing with the SEC other documents regarding the proposed reorganization.  At the appropriate time, the definitive proxy statement/prospectus regarding the proposed reorganization will be mailed to Aon stockholders.

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Before making any voting or investment decision, investors and stockholders are urged to read carefully in their entirety the definitive proxy statement/prospectus regarding the proposed reorganization and any other relevant documents filed by either Aon or Aon UK with the SEC when they become available because they will contain important information about the proposed transaction.  You may obtain copies of all documents filed with the SEC regarding this transaction, free of charge, at the SEC’s website (www.sec.gov) or from Aon by accessing Aon’s website at www.aon.com under the heading “Investor Relations” and then under the link “SEC Filings” or by directing a request to 200 E. Randolph Street, Chicago, Illinois 60601, Attention: Investor Relations.

Aon and Aon UK and their respective directors and executive officers and certain other members of management and employees may be deemed to be participants in the solicitation of proxies in respect of the proposed transaction.  You can find information about Aon’s directors and executive officers in its definitive proxy statement filed with the SEC on April 8, 2011.  Other information regarding the participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC when they become available. You can obtain free copies of these documents using the contact information above.

Explanation of Non-GAAP Measures

This communication includes supplemental information related to organic revenue and several additional measures including expenses, margins and income per share, that exclude the effects of restructuring charges, transaction and integration costs and certain other noteworthy items that affected results for the comparable periods.  Organic revenue excludes from reported revenues the impact of foreign exchange, acquisitions, divestitures, transfers between business units, reimbursable expenses and unusual items.  The impact of foreign exchange is determined by translating last year’s revenue, expense or net income at this year’s foreign exchange rates.  Reconciliations are provided in the attached schedules.  Supplemental organic revenue information and additional measures that exclude the effects of the restructuring charges and certain other items do not affect net income or any other GAAP reported amounts.  Management believes that these measures are important to make meaningful period-to-period comparisons and that this supplemental information is helpful to investors.  They should be viewed in addition to, not in lieu of, the Company’s Consolidated Financial Statements.  Industry peers provide similar supplemental information regarding their performance, although they may not make identical adjustments.

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Aon Corporation

Consolidated Statements of Income (Unaudited)

(1)   Tax rate for continuing operations is 27.0% and 32.8% for the fourth quarters ended December 31, 2011 and 2010, respectively, and 27.3% and 28.4% for the twelve months ended December 31, 2011 and 2010, respectively.

(2)   Tax rate for discontinued operations is not meaningful for the fourth quarter ended December 31, 2011 and 34.0% for the fourth quarter ended December 2010, and 25.7% and 31.8% for the twelve months ended December 31, 2011 and 2010, respectively.

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Aon Corporation

Revenue from Continuing Operations (Unaudited)

(1)          Organic revenue excludes the impact of foreign exchange, acquisitions, divestitures, transfers, reimbursable expenses and unusual items.  Change in organic revenue, a non-GAAP measure, is reconciled to the corresponding U.S. GAAP percent change in revenue on page 13 of this release.

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Aon Corporation

Segments (Unaudited)

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Aon Corporation

Reconciliation of Non-GAAP Measures - Organic Revenue (Unaudited)