Exhibit 99.1

Willis Group Reports Second Quarter 2011 Results

8 percent reported growth and 3 percent organic growth in commissions and fees compared with second quarter of 2010

Reported operating margin of 18.2 percent compared with 21.2 percent in the second quarter of 2010; adjusted operating margin of 21.6 percent, up 20 basis points compared with 21.4 percent in the second quarter of 2010

Reported earnings per diluted share of $0.48 compared with $0.52 in the second quarter of 2010; adjusted earnings per diluted share of $0.61, up 13 percent compared with $0.54 in the second quarter of 2010

NEW YORK--(BUSINESS WIRE)--August 3, 2011--Willis Group Holdings plc (NYSE: WSH), the global insurance broker, today reported results for the quarter and six months ended June 30, 2011.

“We continued to deliver on our plan in the second quarter, recording much of the remaining charge associated with our 2011 operational review and focusing on the implementation of growth initiatives,” said Joe Plumeri, Chairman and Chief Executive Officer, Willis Group Holdings. “The strength of our diversified global business was again shown by our solid 3 percent organic growth in commissions and fees even with continued global economic pressures and little change in the overall rate environment. Delivering on our plan, adjusted operating margin grew modestly to 21.6 percent and adjusted earnings per diluted share grew 13 percent to $0.61.”

Second Quarter 2011 Financial Results

Reported net income for the quarter ended June 30, 2011 was $85 million, or $0.48 per diluted share, compared with $89 million, or $0.52 per diluted share, in the same period a year ago. Reported net income for the second quarter of 2011 was negatively impacted by an $18 million charge related to the 2011 operational review and an $11 million charge related to the previously announced FSA regulatory settlement, as detailed in note 7 of the supplemental financial information.

Adjusted net income per diluted share, which excludes the impact of items detailed in note 7 of the supplemental financial information, was $0.61 in the second quarter of 2011, an increase of 13 percent compared with $0.54 in the second quarter of 2010. Foreign currency movements increased earnings per diluted share by $0.01 compared with the second quarter of 2010.

Total reported revenues for the quarter ended June 30, 2011 were $863 million compared with $799 million for the same period last year, an increase of 8 percent. Total commissions and fees were $854 million, an increase of 8 percent from $789 million in the second quarter of 2010. Foreign currency movements increased reported commissions and fees by 5 percent compared with the year ago period. Investment income was $8 million in the second quarter of 2011, compared with $10 million in the second quarter of 2010.

Organic growth in commissions and fees was 3 percent in the second quarter of 2011 compared with the second quarter of 2010. Organic growth reflected net new business growth of 4 percent driven by higher existing client retention and solid new business generation. Partially offsetting net new business growth was a 1 percent negative impact from declining premium rates and other market factors.

North America Segment

The North America segment reported a 1 percent decline in commissions and fees compared with the second quarter of 2010. Organic growth in commissions and fees was flat in the second quarter of 2011 compared with the second quarter of 2010 which included a $2.9 million benefit from a one-time accounting adjustment related to the HRH acquisition within the specialty businesses. North America delivered low double-digit new business generation and solid client retention. The segment continues to face headwinds from ongoing softness in the insurance rate environment and a lack of sustained improvement in the US economy. Operating margin was 18.6 percent compared to 20.4 percent in the second quarter of 2010, primarily due to flat organic growth in commissions and fees.

International Segment

The International business segment reported 21 percent growth in commissions and fees compared with the same period in 2010, including a 15 percent favorable impact from foreign currency movements. Organic growth in commissions and fees was 6 percent, including double-digit expansion in Latin America and Eastern Europe, while Asia grew high single-digits. Continental Europe, and the UK and Ireland retail market each grew in the low single-digits. Operating margin was 21.5 percent compared with 19.1 percent in the second quarter of 2010. The increase in operating margin was driven by strong growth in organic commissions and fees, together with favorable foreign currency movements, partially offset by higher incentive compensation.

Global Segment

The Global segment, which comprises the Reinsurance, Global Specialties, London Markets Wholesale, and Willis Capital Markets & Advisory business units, reported 9 percent growth in commissions and fees and 3 percent organic growth in commissions and fees in the second quarter of 2011 compared with the second quarter of 2010. Reinsurance and Global Specialties were the drivers of growth in the quarter, partially offset by Willis Capital Markets & Advisory. Reinsurance grew high single digits, with particular strength in North America. Global Specialties’ expansion in the quarter was driven by Aerospace, Financial and Executive Risk, Marine, and Energy. Willis Capital Markets & Advisory had a positive quarter although organic growth in the unit was down significantly from the second quarter of 2010 as that quarter included revenue from a single large capital markets transaction. Operating margin was 32.5 percent in the second quarter of 2011 compared with 34.7 percent in the year ago quarter. The impact of unfavorable foreign currency movements were partially offset by organic growth in commissions and fees and lower pension expense.

Other

Reported salaries and benefits were $506 million in the second quarter of 2011 compared with $456 million in the second quarter of 2010. Salaries and benefits, as a percentage of revenues, were 58.6 percent in the second quarter of 2011 compared with 57.1 percent in the second quarter of 2010. The increase in salaries and benefits included $10 million of severance and other costs associated with the 2011 operational review charge. Excluding the impact of the charge, salaries and benefits as a percentage of revenues would have been 57.5 percent.

The Company made $11 million of cash retention payments in the second quarter of 2011. Incentive compensation included $44 million of amortization of cash retention payments in the second quarter of 2011 compared with $32 million in the second quarter of 2010. As of June 30, 2010, December 31, 2010 and June 30, 2011, the Company included $217 million, $173 million, and $293 million, respectively, in other assets on the balance sheet, which represented the unamortized portion of cash retention payments made before those dates.

Reported other operating expenses were $164 million in the second quarter of 2011 compared with $135 million in the second quarter of 2010. Other operating expenses in the second quarter of 2011 included $11 million related to the previously announced FSA regulatory settlement, and $7 million of costs associated with the 2011 operational review, partly offset by a $9 million release of funds and reserves related to potential legal liabilities. Other operating expenses, as a percentage of revenues, were 19.0 percent in the second quarter of 2011 compared with 16.9 percent in the second quarter of 2010.

Reported operating margin was 18.2 percent for the quarter ended June 30, 2011 compared with 21.2 percent for the same period last year. Excluding certain items, which are detailed in note 6 of the supplemental financial information, adjusted operating margin was 21.6 percent for the quarter ended June 30, 2011 compared with 21.4 percent a year ago. Adjusted operating margin reflects positive organic growth in commissions and fees, offset by unfavorable foreign currency movements and investments to fund growth; including higher incentive compensation.

Six Months 2011 Financial Results

Reported net income for the six months ended June 30, 2011 was $119 million, or $0.68 per diluted share, compared with $293 million, or $1.71 per diluted share, in the same period a year ago. Reported net income for the first six months of 2011 was impacted by certain items, as detailed in note 7 of the supplemental financial information.

Adjusted earnings per diluted share, which excludes the impact of items detailed in note 7 of the supplemental financial information, were $1.89 for the six months ended June 30, 2011 compared with $1.80 in the comparable period of 2010. Foreign currency movements positively impacted adjusted earnings per diluted share by $0.05 in the six months ended June 30, 2011 compared to the same period in 2010.

Total reported revenues for the six months ended June 30, 2011 were $1,871 million compared with $1,771 million for the same period last year, an increase of 6 percent. Total commissions and fees were $1,854 million, an increase of 6 percent from $1,752 million for the first six months of 2010. Foreign currency movements increased reported commissions and fees by 3 percent compared with the same period in 2010.

Organic growth in commissions and fees was 3 percent in the first half of 2011 compared with the comparable period of 2010. This growth reflected net new business won of 4 percent partially offset by a negative 1 percent impact from declining premium rates and other market factors.

Reported operating margin was 21.1 percent for the six months ended June 30, 2011 compared with 26.5 percent for the same period last year. Excluding items detailed in note 6 of the supplemental financial information, adjusted operating margin was 27.6 percent for the first half of 2011 compared with 27.3 percent a year ago.

2011 Operational Review

The Company recorded a pre-tax charge of $18 million in the second quarter of 2011 and $115 million in the six months ended June 30, 2011 related to the previously announced operational review. The Company continues to anticipate that the total pre-tax charge in 2011 related to the operational review will be approximately $130 million.

The Company anticipates that the operational review will result in total cost savings of approximately $65 to $75 million in 2011. It is also anticipated that the Company will achieve annualized cost savings of approximately $95 to $105 million beginning in 2012.

Tax

The tax rate was 25 percent for the quarter ended June 30, 2011 and 21 percent for the six months ended June 30, 2011. Excluding the impact of nonrecurring items, the underlying tax rate for the quarter and six months ended June 30, 2011 was also 25 percent, lower than the 26 percent underlying tax rate for the full year 2010.

Capital

As of June 30, 2011, cash and cash equivalents totaled $317 million and total debt was $2.4 billion.

In the second quarter of 2011, the Company completed the previously-announced redemption of $35 million of 12.875% Senior Notes due 2016 that remained outstanding.

Total equity was $2.7 billion.

Dividends

The Board of Directors declared a regular quarterly cash dividend on the Company’s ordinary shares of $0.26 per share (an annual rate of $1.04 per share). The dividend is payable on October 14, 2011 to shareholders of record on September 30, 2011.

Conclusion

“I am proud of the work done by all of our associates to deliver another quarter of solid financial results. With the challenges from the external environment remaining largely the same, especially the lack of improvement in global economic conditions, our efforts will remain focused on achieving planned cost savings from our 2011 operational review and implementing our revenue initiatives to drive future growth,” said Mr. Plumeri.

Conference Call and Web Cast

A conference call to discuss the second quarter 2011 results will be held on Thursday, August 4, 2011, at 8:00 AM Eastern Time. To participate in the live teleconference, please dial (866) 803-2143 (domestic) or +1 (210) 795-1098 (international) with a pass code of “Willis”. The live audio web cast (which will be listen-only) may be accessed on the Investor Relations page on www.willis.com. This call will be available by replay starting at approximately 10:00 AM Eastern Time, and through September 4, 2011 at 11:59 PM Eastern Time, by calling (866) 458-4762 (domestic) or +1 (203) 369-1319 (international) with no pass code, or by accessing the website.

About Willis

Willis Group Holdings plc is a leading global insurance broker. Through its subsidiaries, Willis develops and delivers professional insurance, reinsurance, risk management, financial and human resource consulting and actuarial services to corporations, public entities and institutions around the world. Willis has more than 400 offices in nearly 120 countries, with a global team of approximately 17,000 employees serving clients in virtually every part of the world. Additional information on Willis may be found at www.willis.com.

Forward-Looking Statements

We have included in this document ‘‘forward-looking statements’’ within the meaning of Section 27A of the Securities Act of 1933, and Section 21E of the Securities Exchange Act of 1934, which are intended to be covered by the safe harbors created by those laws. These forward-looking statements include information about possible or assumed future results of our operations. All statements, other than statements of historical facts that address activities, events or developments that we expect or anticipate may occur in the future, including such things as our outlook, potential cost savings and acceleration of adjusted operating margin and adjusted earnings growth, future capital expenditures, growth in commissions and fees, business strategies, competitive strengths, goals, the benefits of new initiatives, growth of our business and operations, plans and references to future successes, are forward-looking statements. Also, when we use the words such as ‘‘anticipate’’, ‘‘believe’’, ‘‘estimate’’, ‘‘expect’’, ‘‘intend’’, ‘‘plan’’, ‘‘probably’’, or similar expressions, we are making forward-looking statements.

There are important uncertainties, events and factors that could cause our actual results or performance to differ materially from those in the forward-looking statements contained in this document, including the following:

• the impact of any regional, national or global political, economic, business, competitive, market, environmental, and regulatory conditions on our global business operations;
• the impact of current financial market conditions on our results of operations and financial condition, including as a result of any insolvencies of or other difficulties experienced by our clients, insurance companies or financial institutions;
• our ability to continue to manage our significant indebtedness;
• our ability to compete effectively in our industry;
• our ability to implement and realize anticipated benefits of the 2011 Operational Review, the Willis Cause or any other initiative we pursue;
• material changes in commercial property and casualty markets generally or the availability of insurance products or changes in premiums resulting from a catastrophic event, such as a hurricane, or otherwise;
• the volatility or declines in other insurance markets and premiums on which our commissions are based, but which we do not control;
• our ability to retain key employees and clients and attract new business;
• the timing or ability to carry out share repurchases, refinancings or take other steps to manage our capital and the limitations in our long-term debt agreements that may restrict our ability to take these actions;
• any fluctuations in exchange and interest rates that could affect expenses and revenue;
• rating agency actions that could inhibit our ability to borrow funds or the pricing thereof;
• a significant decline in the value of investments that fund our pension plans or changes in our pension plan funding obligations;
• our ability to achieve the expected strategic benefits of transactions;
• our ability to receive dividends or other distributions in needed amounts from our subsidiaries;
• changes in the tax or accounting treatment of our operations;
• any potential impact from the US healthcare reform legislation;
• the potential costs and difficulties in complying with a wide variety of foreign laws and regulations and any related changes, given the global scope of our operations;
• our involvements in and the results of any regulatory investigations, legal proceedings and other contingencies;
• risks associated with non-core operations including underwriting, advisory or reputational;
• our exposure to potential liabilities arising from errors and omissions and other potential claims against us; and
• the interruption or loss of our information processing systems or failure to maintain secure information systems.

The foregoing list of factors is not exhaustive and new factors may emerge from time to time that could also affect actual performance and results. For more information see the section entitled ‘‘Risk Factors’’ included in Willis’ Form 10-K for the year ended December 31, 2010 and our subsequent filings with the Securities and Exchange Commission. Copies are available online at http://www.sec.gov or www.willis.com or on request from the Company as set forth in Part I, Item 1 “Business-Available Information” in Willis’ Form 10-K.

Although we believe that the assumptions underlying our forward-looking statements are reasonable, any of these assumptions, and therefore also the forward-looking statements based on these assumptions, could themselves prove to be inaccurate. In light of the significant uncertainties inherent in the forward-looking statements included in this document, our inclusion of this information is not a representation or guarantee by us that our objectives and plans will be achieved.

Our forward-looking statements speak only as of the date made and we will not update these forward-looking statements unless the securities laws require us to do so. In light of these risks, uncertainties and assumptions, the forward-looking events discussed in this document may not occur, and we caution you against unduly relying on these forward-looking statements.

Non-GAAP Supplemental Financial Information

This press release contains references to non-GAAP financial measures as defined in Regulation G of SEC rules. Consistent with Regulation G, a reconciliation of this supplemental financial information to our GAAP information is in the note disclosures that follow. We present such non-GAAP supplemental financial information, as we believe such information is of interest to the investment community because it provides additional meaningful methods of evaluating certain aspects of the Company’s operating performance from period to period on a basis that may not be otherwise apparent on a GAAP basis. This supplemental financial information should be viewed in addition to, not in lieu of, the Company’s condensed financial statements.

CONTACT:
Willis Group Holdings plc
Investors:
Mark Jones, 212-915-8796
mark.p.jones@willis.com
or
Media:
Ingrid Booth, +44 203 124-7182
boothi@willis.com