SecProbe.io

Mail Stop 3720

April  12, 201 7

Philip J. Angelastro
Chief Financial  Officer
Omnicom Group, Inc.
437 Madison Avenue
New York, NY  10022

Re: Omnicom Group, Inc.
 Form 10 -K for Fiscal Year Ended December 31, 2016
Filed February 9, 2017
  File No. 001-10551

Dear Mr. Angelastro :

We have limited our review of your filing to the financial statements and related
disclosures and have the following comments.  Please comply with these comments in future
filings.  Confirm in writing that you will do so and explain to us how you intend to comply.  In
some of our comments, we may ask you to provide us with information so we may better
understand your disclosure.

Please r espond to these comments within ten business days by providing the requested
information or advise us as soon as possible when you will respond.  If you do not believe our
comments apply to your facts and circumstances, please tell us why in your response.

After reviewing your response to these comments, we may have additional comments.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of
Operations , page 9

Results of Operations – 2016 Compared to 2015 , page 1 5

1. Please revise the reconciliation of the non -GAAP measure EBITA to begin with net
income, the most directly comparable GAAP financial measure.  Your current
presentation places greater prominence on the non -GAAP measure and is inconsistent
with Question 102.10 of the updated Compliance and Disclosure Interpretation Guidance
on non -GAAP financial measures issued on May 17, 2016.   In addition, please revise
your presentation in your next earnings release.

Philip J. Angelastro
Omnicom Group, Inc.
April  12, 2017
Page 2

 2. We note your disclosures of the components of reven ue change on page 15.  Please
disclose in more detail how you calculate the amount s identified as  Acquisitions, net of
dispositions, why it is calculated in this manner and why y ou believe this measure
provide s useful information to investors.  In addition , provide a table showing the
components that make up your calculation of Acquisitions, net of disposition s.

3. Regarding your measure of organic growth, please disclose why management is
apparently attributing any positive developments in an acquired busi ness that may have
taken place during the period preceding the acquisition to organic growth .  Explain how
investors should consider this circumstance when assessing performance using your
measure of organic growth.

Financial Statements
7. Segment Reporting, page F -17

4. We note you determined that your five branded agency networks comprise your operating
segments which meet the criteria for aggregation since the segments have similar
operating and economic characteristics.   To help us understand how you applied the
guidance in FASB ASC 280, please provide us with the following information:

 a comparison and contrast of your operating segments relative to the areas listed in
ASC 280 -10-50-11(a) to (e);
 your consideration of differences among your o perating segments and why you
determined that disaggregation was not warranted;
 how the primary service offering of each branded agency network and respective
brand distinction are considered in your aggregation analysis ;
 each branded network’s historical  and projected revenues, gross margin, operating
margin, and measure of segment profitability; and
 an explanation of  why the company is organized in the manner that it is.

We remind you that the company and its management are responsible for the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action or absence of
action by the staff.

Philip J. Angelastro
Omnicom Group, Inc.
April  12, 2017
Page 3

 You may contact Kathryn T. Jacobson, Senior Staff Accountant  at (202) 551 -3365  or
Robert S. Lit tlepage, Accountant Branch Chief  at (202) 551 -3361  or me at (202) 551 -3810 with
any questions.

Sincerely,

 /s/ Robert S. Littlepage, for

 Carlos Pacho
Senior Assistant Chief Accountant
 AD Office 11 – Telecommunications