Basis of Presentation

The accompanying Consolidated Financial Statements and Notes thereto have been prepared in accordance with U.S. generally accepted accounting principles ("U.S. GAAP"). The Consolidated Financial Statements include the accounts of Aon plc and all of its controlled subsidiaries ("Aon" or the "Company"). All intercompany accounts and transactions have been eliminated. The Consolidated Financial Statements include, in the opinion of management, all adjustments necessary to present fairly the Company's consolidated financial position, results of operations and cash flows for all periods presented.

Reclassification

Certain amounts in prior years' Consolidated Financial Statements and related notes have been reclassified to conform to the 2015 presentation.

In prior periods, long-term investments were included in Investments in the Consolidated Statement of Financial Position. These amounts are now included in Other non-current assets in the Consolidated Statement of Financial Position, as shown in Note 3 to these Consolidated Financial Statements. Long-term investments were $135 million at December 31, 2015 and $143 million at December 31, 2014.

In prior periods, prepaid pensions were included in Other non-current assets in the Consolidated Statement of Financial Position. These amounts are now separately disclosed in the Consolidated Statement of Financial Position. Prepaid pensions were $1,033 million at December 31, 2015 and $933 million at December 31, 2014.

Upon vesting of certain share-based payment arrangements, employees may elect to use a portion of the shares to satisfy tax withholding requirements, in which case Aon makes a payment to the taxing authority on the employee’s behalf and remits the remaining shares to the employee. The Company has historically presented amounts due to taxing authorities within Cash Flows From Operating Activities in the Consolidated Statements of Cash Flows. The amounts are now included in “Issuance of shares for employee benefit plans” within Cash Flows From Financing Activities. The Company believes this presentation provides greater clarity into the operating and financing activities of the Company as the substance and accounting for these transactions is that of a share repurchase. It also aligns the Company’s presentation to be consistent with industry practice. Amounts reported in Issuance of shares for employee benefit plans were $227 million, $170 million, and $120 million, respectively, for the years ended December 31, 2015, 2014 and 2013. These amounts, which were reclassified from Accounts payable and accrued liabilities and Other assets and liabilities, were $85 million and $85 million in 2014, and $62 million and $58 million in 2013, respectively.

Changes to the presentation in the Consolidated Statements of Cash Flows for 2014 and 2013 were made related to certain line items within financing activities. The following line items and respective amounts have been aggregated in a new line item titled “Noncontrolling interests and other financing activities” within financing activities.



Years Ended December 31,	2014		2013
Purchases of shares from noncontrolling interests	3		(8	)
Dividends paid to noncontrolling interests	(24	)	(19	)
Proceeds from sale-leaseback	25		—

Use of Estimates

The preparation of the accompanying Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of reserves and expenses. These estimates and assumptions are based on management's best estimates and judgments. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment. Management believes its estimates to be reasonable given the current facts available. Aon adjusts such estimates and assumptions when facts and circumstances dictate. Illiquid credit markets, volatile equity markets, and foreign currency exchange rate movements increase the uncertainty inherent in such estimates and assumptions. As future events and their effects cannot be determined, among other factors, with precision, actual results could differ significantly from these estimates. Changes in estimates resulting from continuing changes in the economic environment would, if applicable, be reflected in the financial statements in future periods.