POWER OF ATTORNEY

I,  Lester B. Knight ("Grantor"), hereby confirm, constitute and appoint each of
Michael  Wolf,  Michele  Welsh and Molly Johnson, or any of them signing singly,
and  with full power of substitution, as the true and lawful attorney-in-fact of
Grantor to:

      prepare,  execute in Grantor's name and on Grantor's behalf, and submit to
      the  United  States  Securities and Exchange Commission (the "SEC") a Form
      ID,  including  amendments  thereto,  and any other documents necessary or
      appropriate to obtain codes and passwords enabling the undersigned to make
      electronic  filings  with  the SEC of reports required by Section 16(a) of
      the  Securities  Exchange  Act of 1934, as amended (the "Exchange Act") or
      any rule or regulation promulgated by the SEC;

      execute for and on behalf of Grantor, in Grantor's capacity as an officer,
      director  or  greater  than  ten  percent  shareholder  of  Aon  plc  (the
      "Company"),  Forms 3, 4 and 5, including but not limited to any amendments
      thereto,  in  accordance  with  Section 16(a) of the Exchange Act, and the
      rules  promulgated  thereunder,  which  may be necessary or desirable as a
      result  of  Grantor's  ownership  of  or  transaction in securities of the
      Company; and

      do  and perform any and all acts for and on behalf of Grantor which may be
      necessary  or desirable to complete and execute any such Form 3, 4 or 5 or
      any  amendments  thereto,  and  timely file such form with the SEC and any
      other stock exchange or similar authority.

Grantor  hereby grants to each such attorney-in-fact full power and authority to
do  and  perform  any and every act and thing whatsoever requisite, necessary or
proper  to  be  done  in  the  exercise  of  any of the rights and powers herein
granted,  as fully to all intents and purposes as the undersigned might or could
do  if personally present, with full power of substitution or revocation, hereby
ratifying   and   confirming   all   that   such   attorney-in-fact,   or   such
attorney-in-fact's  substitute  or substitutes, shall lawfully do or cause to be
done  by  virtue  of  this  power  of  attorney and the rights and powers herein
granted.  Grantor  acknowledges that the foregoing attorneys-in-fact, in serving
in such capacity at the request of Grantor, are not assuming, nor is the Company
assuming,  any  of  Grantor's  responsibilities to comply with Section 16 of the
Exchange Act.

This  Power of Attorney shall be effective on the date set forth below and shall
continue in full force and effect until the date on which Grantor shall cease to
be  subject  to  Section  16  of  the  Exchange  Act  and  the rules promulgated
thereunder  or until such earlier date on which written notification executed by
Grantor is filed with the SEC expressly revoking this Power of Attorney.

IN  WITNESS WHEREOF, Grantor has caused this Power of Attorney to be executed as
of this 18 day of November, 2016

Signature:           /s/ Lester B. Knight
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