Peter Lieb
Aon Corporation
United States

April 26, 2016

International Assignment: Chicago, Illinois (U.S.) to London, England

Dear Peter,

This international assignment letter (this “Letter”) restates and extends the
term of your international assignment from Chicago, Illinois to London, England.
Unless otherwise explicitly provided herein, this Letter shall govern the terms
and conditions of your assignment from July 1, 2016 through June 30, 2018 (the
“Term”), and during the Term shall supersede in their entirety both the letter
entered into between you and Aon Corporation (the “Company”) dated January 12,
2012 and the extension letter entered into between you and the Company dated
July 1, 2014 (collectively, your “Prior Assignment Letter”). The terms and
conditions of your Prior Assignment Letter shall continue to apply through June
30, 2016.

We are committed to working with you to ensure that your international
assignment continues to be as successful and effectively managed as possible.
This Letter sets out the terms of your assignment and the assistance we are
committed to provide in connection with your assignment, consistent with the
approval of, and directions provided by, the Organization and Compensation
Committee of the board of directors of Aon plc.

1.
Introduction

Your continued assignment is subject to your acceptance of the terms and
conditions outlined in this Letter, which sets forth the entire agreement
between you and the Company regarding your international assignment. To the
extent that anything in this Letter conflicts with the employment agreement
entered into between you and the Company dated January 1, 2014 (the “Employment
Agreement”) or the Company's employment-related policies and practices
generally, this Letter, once countersigned by you, will be a variation to
your employment terms. Unless otherwise specified herein, your
current employment terms and conditions will remain unchanged for the duration
of the international assignment.

2.
Assignment Duration

Once the Term is completed, you will return to the Company's offices in
Chicago, Illinois, provided that the Company may, in consultation with
you, extend or shorten your assignment and the Term according to business needs
and/or your personal circumstances. Notwithstanding the foregoing, in the event
that your assignment is extended beyond 36 months from the beginning of the
Term, the Company reserves the right to "localize" your term by maintaining your
international assignment and terminating the Term under this Letter.

3.
Immigration

Your assignment is conditional upon the Company being able to obtain and
maintain the appropriate work permit, visa and/or other authorization documents
for you to work and remain in London, England. The Company will cover the cost
of obtaining and maintaining the appropriate work permit/visa for you. In
addition, should you wish, the Company will also assist your spouse or partner
in obtaining a work permit, visa and/or other authorization documents to work in
London.

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4.
Changes to Compensation Arrangements

The changes to your compensation and benefits package during your international
assignment, as described below, are designed to provide you with a level of
income and benefits which do not disadvantage you in comparison to those you
would have received in the United States. We have also taken into consideration
any additional costs that you may reasonably incur as a result of living in
London. Unless otherwise noted below as being an excluded or non-taxable
benefit, the following benefits will be grossed up for applicable taxes to
compensate you for any tax differential according to the Company’s tax
equalization policy for international assignments (as described in Appendix A).

4.1
Foreign Service Allowance

During the Term, you will receive an annual foreign service allowance of
US$105,000. While on assignment, your annual foreign service allowance will be
added to your base salary for purposes of determining your annual target
incentive opportunity. The allowance will be paid semi-monthly via your
U.S. payroll.

4.2
Housing Allowance

During the Term, you will receive an annual housing allowance of US$286,510 (a
monthly allowance of US$23,876). The allowance is to be used to pay
accommodation and furniture rental costs and associated utility costs (excluding
telephone and internet access which are personal expenses). This allowance will
be reviewed annually and may be adjusted to reflect foreign exchange and local
market rate variation, and will be paid semi-monthly via your U.S. payroll. The
Company will not be responsible in any way for your current residence in your
home location. The payment of your U.S. housing expenses will remain your
responsibility.

4.3
Cost of Living Allowance

During the Term, you will receive an annual cost of living allowance of
US$97,500. This allowance will be reviewed annually and may be adjusted to
reflect foreign exchange and local market rate variation, and will be paid
semi-monthly via your U.S. payroll.

4.4
Car Allowance

During the Term, you will receive an annual car allowance of US$23,500. This
allowance will be paid semi-monthly via your U.S. payroll.

4.5
Home Leave Allowance

You and each family member that has relocated or is relocating with you are
entitled to one round-trip home leave to return to the U.S. for each complete
year you are on assignment. In addition, any immediate family members (e.g.,
university aged dependent children) not accompanying you on assignment are
entitled to two round-trip flights to the U.K. for each complete year you are on
assignment.

4.6
Income Taxes Payable in the U.K. (Equalization Tax)

It is likely that all or a portion of your earned income during any given U.K.
tax year will be subject to tax in the U.K. The Company applies a tax
equalization policy (as described in Appendix A) which is designed to ensure the
income and social taxes you pay will be no more than what you would have paid
had all of your earnings been taxable solely in the U.S.

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4.7
Tax Preparation Services

The Company will also provide you with enhanced tax preparation, financial
planning and expatriate services for the tax years covered by the international
assignment and tax years for which international earnings are taxed by U.K. tax
authorities following repatriation at the conclusion of the Term (or upon your
termination of employment without Cause or for Good Reason while on assignment)

5.
Hours of Work and Holidays

Your work schedule, work hours and observed holidays will follow the practice in
London.

6.
Repayment Agreement

Should you elect to resign from the Company to work with a direct competitor,
during your assignment or up to 12 months after the end of the Term, the Company
reserves the right to require repayment of all expatriate allowances you
received in the preceding 12 months. You agree that the Company may set off any
such amounts against any amount the Company owes you on or after termination of
your employment.

Should you depart the Company due to mutual consent or for Good Reason (as
defined in your Employment Agreement) or if a comparable U.S.-based role is not
available at the completion of your assignment, this repayment agreement will
not apply.

7.
Termination of Employment

Notwithstanding the foregoing, if your employment is terminated without Cause or
for Good Reason (as such terms are defined in your Employment Agreement) during
the Term, the following provisions will apply during the Term and thereafter for
as long as you continue to abide by the conditions of Section 5(b) and 5(c) of
your Employment Agreement, comply in all material respects with Section 7 of
your Employment Agreement, and sign and return the release required under
Section 4(b)(ii) of your Employment Agreement, in each case, as and to the
extent provided as follows:

•
Your cost of living and home leave allowances (and all tax gross-ups thereon)
will continue through the Termination Date (as defined in the Employment
Agreement).

•
Your housing and car allowances (and all tax gross-ups thereon) will continue
until the later to occur of (1) the Termination Date or (2) the date of
termination or expiration of any agreement, commitment or arrangement pursuant
to which you have obtained such housing or car (it being understood that if the
Company requires you to leave the premises on the Notice Date (as defined in the
Employment Agreement) or otherwise informs you that you will not be required to
perform any further services prior to the Termination Date, that you will not
take any action thereafter to extend such agreement, commitment or arrangement
other than to extend the arrangement to the Termination Date) and will use your
reasonable efforts to mitigate the cost of termination of any such agreement,
commitment or arrangement following the Termination Date (but without obligation
for you to incur cost in doing so).

•
Your tax preparation, financial planning and tax equalization benefits will
continue for all periods in which you receive income attributable to the period
of assignment (including all compensation, earnings recognized on the granting
or vesting of equity-based awards and benefits received under or contemplated by
the Employment Agreement, the Executive Committee Combined Severance and Change
in Control Plan (as amended from time to time), or this Letter before or after
the Termination Date) and such benefits will be considered earned and vested on
the Termination Date. Notwithstanding the foregoing, this provision shall also
apply in the event that your employment is terminated due to your resignation
after attaining age 55.

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For the avoidance of doubt, should you be terminated for Cause or voluntarily
terminate your employment without mutual consent while on assignment, you will
bear all relocation and other costs arising after your termination for Cause or
resignation date.

8.
Completion of Assignment

At the end of your assignment, the Company will endeavor to repatriate you into
a position consistent with your then current employment agreement, if
applicable, and in accordance with your capabilities, interest and career
potential. Your relocation will be managed in accordance with the
provisions of the Company's policy.

9.
Repatriation Assistance

The Company will pay the transportation and moving cost for you and your family
back to the U.S. at the end of the Term (or once your assignment ends due to
your termination of employment without Cause or for Good Reason, or due to your
resignation after attaining age 55) in accordance with the Company's
international relocation policy.

10.
Third Party Beneficiary

Each related entity of the Company is a third party beneficiary of this Letter,
and each of them has the full right and power to enforce rights, interests and
obligations under this Letter without limitation or other restriction.

11.
No Waiver

No failure or delay by any party in exercising any right, power or remedy under
this Letter shall operate as a waiver thereof, nor shall any single or
particular exercise of the same preclude any further exercise thereof
or the exercise of any other right, power or remedy. Without limiting
the foregoing, no waiver by any party of any breach of any provision of this
Letter shall be deemed to be a waiver of any subsequent breach of that or any
other provision of this Letter.

12.
Withholding and Deductions

While it is anticipated that all or most of your compensation from the Company
will be subject to a hypothetical tax deduction rather than
actual tax withholdings, all amounts paid pursuant to this Letter shall be
subject to deductions and withholding for taxes (national, local, foreign or
otherwise) to the extent required by applicable law.

13.
Code Section 409A

We intend that this Letter and the benefits provided hereunder be interpreted
and construed to be exempt from or otherwise comply with the applicable
requirements of Section 409A of the U.S. Internal Revenue Code of 1986, as
amended, and all Treasury regulations and guidance issued thereunder ("Code
Section 409A"), including the exceptions for short-term deferrals, separation
pay arrangements, reimbursements, and in-kind distributions. To the extent that
any provision of this Letter would fail to comply with the applicable
requirements of Code Section 409A, the Company may, in its sole and absolute
discretion and without requiring your consent, make such modifications to the
Letter and/or payments to be made thereunder to the extent it determines
necessary or advisable to comply with the requirements of Code Section 409A.
Notwithstanding any provision of this Letter to the contrary, if you are a
“specified employee” within the meaning of Code Section 409A, any payments or
arrangements due upon a termination of your employment that are subject to the
requirements of Code Section 409A shall be delayed and paid or provided on the
earlier of six months after your termination of employment or the date of your
death. Upon the expiration of this delay period, all payments and benefits
delayed shall be paid or reimbursed to you in a lump sum, and any remaining
payments and benefits due under this Letter shall be paid or provided in
accordance with the

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terms of this Letter. For purposes of applying the provisions of Code Section
409A, each separately identifiable amount to which you are entitled will be
treated as a separate payment. A termination of employment shall not be deemed
to have occurred for purposes of any provision of this Letter providing for
payment of amounts subject to Code Section 409A upon or following a termination
of employment unless the termination is also a “separation from service” under
Code Section 409A.

14.
Governing Law

This Letter will be construed in accordance with and governed by the laws of the
State of Illinois, without regard to the choice of law principles thereof. Any
suit, action or other legal proceeding arising out of or relating to this
Letter shall be brought exclusively in the Federal or state courts located in
the State of Illinois. You agree to submit to personal jurisdiction in the
foregoing courts and to venue in those courts. You further agree to waive all
legal challenges and defenses to the propriety of a forum in Chicago, Illinois
and to the application of Federal or Illinois law therein.

Please confirm acceptance of the terms set out in this Letter by signing below
and returning a copy of the signed Letter to me.

Sincerely,

/s/ Anthony R. Goland

Anthony R. Goland
EVP, Chief Human Resources Officer

Employee's Acknowledgement:

By signing below, I acknowledge receipt of this Letter; I accept the terms and
conditions contained herein; and I consent to this international
assignment. For the avoidance of doubt, nothing in this Letter is intended to
diminish my rights under my Employment Agreement, or any plan or equity-based
award agreement, and I will continue to be entitled to the rights and benefits
under any such arrangement during this international assignment. Notwithstanding
the foregoing, I acknowledge and agree that my consent herein to the
international assignment, and my acceptance of this particular international
assignment to London and my repatriation thereafter, shall not give rise to any
right to terminate for Good Reason (as defined in my Employment Agreement, if
applicable, or any other agreement between me and the Company) now or hereafter.

I further acknowledge that I have read and agree to be bound by the Company's
tax equalization policy (as set forth on Appendix A). With regard to that
policy, I specifically agree acknowledge and agree that: if I owe any monies to
the Company I will make payment of such monies to the Company within 60 days of
receiving notification of the amount due; and authorize the Company to deduct
(or reduce from my earnings) any amounts owed under this policy from my paycheck
where permitted by law.

Peter Lieb  

Date          

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Appendix A

Tax Equalization Policy

The Company will apply the following tax equalization policy to ensure that the
income and social taxes you pay will be no more than that you would have paid
had all of your earnings been taxable solely in the U.S. For the avoidance of
doubt, the policy does not provide for the grossing up for U.S. income and
social taxes on the relocation benefits described in the Letter.

The Company will determine an estimate of the tax liability you would have paid
in the U.S. on your earnings from the Company, known as your "hypothetical'' tax
liability, and will deduct this estimated hypothetical tax from your monthly
earnings via the Company's U.S. payroll. This policy will not protect you in
your capacity as a shareholder of the Company from capital gains recognized
pursuant to U.S. federal income tax as a result of the merger; however, your
earnings related to granting or vesting of equity-based awards during your
international assignment will be covered by this policy.

Hypothetical tax is paid on salary and on any other income paid to you by the
Company (e.g. bonus) or compensation recognized by you (e.g., granting or
vesting of stock-based incentives). Please note, for the avoidance of doubt, the
Company will deduct hypothetical tax from your income at the point the income is
paid to you and not by reference to the payment date that might have applied had
you not taken up the assignment.

Please note that you will be responsible for the cost of any tax or additional
charges arising in any tax jurisdiction on any personal income or gains, spousal
income or any other U.S. source income.

For the duration of your assignment and any tail period required, the Company
will authorize and pay for a tax adviser to: (1) prepare your joint or
individual U.S. Federal and State, and U.K. tax returns as required; and (2),
reconcile the hypothetical tax deductions made from your earnings.

If the amount of your final hypothetical tax liability to the Company is greater
than the amount of any estimated hypothetical tax payments deducted by the
Company from your salary or other payments, then you will be required to pay the
additional hypothetical tax to the Company within 60 days of the
relevant tax returns being finalized. If it is less, then the Company will
reimburse any excess to you within 60 days.

Provided you meet your obligations to the Company in respect. of your
hypothetical fax liability and provide such information and assistance as the
Company and/or its designated tax adviser shall require in order to
resolve your tax affairs on a timely basis and within the filing deadlines set
down by the applicable tax authorities, the Company will pay any actual tax or
social security liability arising in respect of your earned income.

Should you delay providing the necessary information to the tax advisers you
will be responsible for any additional fees and/or penalties that arise as a
result of the delay.

Although the Company will retain and pay all external tax adviser on your behalf
to prepare your tax returns and to calculate your· tax equalization
calculations, it remains your personal obligation to file such returns within
the applicable time limits and to abide by the tax laws in both the U.S. and
U.K. The external tax adviser will provide regular information regarding your
obligations and filing schedules.