POWER OF ATTORNEY

      Known all by these presents, that the undersigned hereby
constitutes and appoints each of Christopher L. Gaenzle,
Donald R. Reynolds and S. Halle Vakani, and each of them
acting alone, signing singly, the undersigned's true and
lawful attorney-in-fact to:  (1) execute for and on behalf
of the undersigned, in the undersigned's capacity as an officer,
director and/or 10% or more stockholder of INC Research Holdings, Inc.
(the "Company"), Forms ID, 3, 4, 5 and Update Passphrase Acknowledgement
(and any amendments thereto) in accordance with Section 16(a) of the
Securities Exchange Act of 1934, as amended (the "1934 Act"), and the
rules promulgated thereunder; (2) do and perform any and all acts for
and on behalf of the undersigned which may be necessary or desirable to
complete and execute any such Form ID, 3, 4, 5 and Update Passphrase
Acknowledgement (and any amendments thereto) and to file timely such
form with the United States Securities and Exchange Commission and
any stock exchange or similar authority; and (3) take any other
action of any type whatsoever in connection with the foregoing
which in the opinion of such attorney-in-fact may be of benefit to,
in the best interest of, or legally required by, the undersigned,
it being understood that the documents executed by such
attorney-in-fact on behalf of the undersigned pursuant to this
Power of Attorney shall be in such form and shall contain such terms
and conditions as such attorney-in-fact may approve in such
attorney-in-fact's discretion.

     The undersigned 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.  The undersigned acknowledges that the
foregoing attorneys-in-fact, in serving in such capacity at the request
of the undersigned, are not assuming, nor is the Company assuming,
any of the undersigned's responsibilities to comply with Section 16
of the 1934 Act.

    This Power of Attorney shall remain in full force and effect
until the undersigned is no longer required to file Forms ID, 3, 4
and 5 with respect to the undersigned's holdings of and transactions
in securities issued by the Company, unless earlier revoked by the
undersigned in a signed writing delivered to each of the foregoing
attorneys-in-fact.

    IN WITNESS WHEREOF, the undersigned has caused this
Power of Attorney to be executed as of this 15th day of
January 2015.



/s/ David Y. Norton