Exhibit 10.1

INCREMENTAL ASSUMPTION AGREEMENT dated as of September 3, 2015 (this “ Agreement ”), among CBRE SERVICES, INC., a Delaware corporation (the “ U.S. Borrower ”), CBRE LIMITED, a limited company organized under the laws of England and Wales (with company no: 3536032) (the “ U.K. Borrower ”), CBRE LIMITED, a corporation organized under the laws of the province of New Brunswick (the “ Canadian Borrower ”), CBRE PTY LIMITED, a company organized under the laws of Australia and registered in New South Wales (the “ Australian Borrower ”), CBRE LIMITED, a company organized under the laws of New Zealand (the “ New Zealand Borrower ” and, together with the U.S. Borrower, the U.K. Borrower, the Canadian Borrower and the Australian Borrower, the “ Borrowers ”), CBRE GROUP, INC., a Delaware corporation (“ Holdings ”), the INCREMENTAL TRANCHE B-1 TERM LENDERS party hereto, the INCREMENTAL TRANCHE B-2 TERM LENDERS party hereto and CREDIT SUISSE AG, as Administrative Agent.

A.         Reference is made to the Second Amended and Restated Credit Agreement dated as of January 9, 2015 (as amended by Amendment No. 1 dated as of May 28, 2015, and as further amended, supplemented or modified prior to the date hereof, the “ Credit Agreement ”), among the Borrowers, Holdings, the Lenders (as defined in Article I of the Credit Agreement) and Credit Suisse AG, as administrative agent (in such capacity, the “ Administrative Agent ”) and as collateral agent (in such capacity, the “ Collateral Agent ”) for the Lenders.

B.         Holdings and the U.S. Borrower have requested that (i) the persons set forth on Schedule II hereto (together with their permitted successors and assigns, the Incremental Tranche B-1 Term Lenders ”) commit to make Incremental Term Loans (the “ Incremental Tranche B-1 Term Loans ”) to the U.S. Borrower on the B-1 Funding Date (as defined below in Section 1) in an aggregate principal amount of up to $270,000,000 and (ii) the persons set forth on Schedule III hereto (together with their permitted successors and assigns, the “ Incremental Tranche B-2 Term Lenders ” and, together with the Incremental Tranche B-1 Term Lenders, the “ New Incremental Term Lenders ”) commit to make Incremental Term Loans (the “ Incremental Tranche B-2 Term Loans ” and, together with the Incremental Tranche B-1 Term Loans, the “ New Incremental Term Loans ”) to the U.S. Borrower on the B-2 Funding Date (as defined below in Section 1) in an aggregate principal amount of up to $130,000,000, the proceeds of such New Incremental Term Loans to be used to pay fees and expenses relating to the New Incremental Term Loans and for general corporate purposes, including, without limitation, paying the consideration for the acquisition of the Global WorkPlace Solutions business of Johnson Controls, Inc. (the “ Radio Acquisition ”).

C.         The New Incremental Term Lenders are willing to make the New Incremental Term Loans to the U.S. Borrower, in each case on the relevant Funding Date (as defined below in Section 1) and on the terms and subject to the conditions set forth herein and in the Credit Agreement.

Accordingly, in consideration of the mutual agreements herein contained and for other good and valuable consideration, the sufficiency and receipt of which are hereby acknowledged, the parties hereto agree as follows:

SECTION 1.     Terms Generally .   (a) The rules of construction set forth in Section 1.02 of the Credit Agreement shall apply mutatis mutandis to this Agreement. This Agreement shall be a “Loan Document” for all purposes of the Credit Agreement and the other Loan Documents and, to the extent it relates to the making of New Incremental Term Loans, an “Incremental Assumption Agreement” for all purposes of the Credit Agreement and the other Loan Documents. Capitalized terms used but not defined herein have the meanings assigned thereto in the Credit Agreement.

(b)        As used in this Agreement, the following terms have the meanings specified below:

“ B-1 Funding Date ” shall mean the date, on or after the Effective Date (as defined below in Section 5) and prior to the New Incremental Term Loan Commitment Termination Date (as defined below in Section 2), on which (a) all of the conditions precedent set forth in Section 6 are satisfied and (b) the Incremental Tranche B-1 Term Loans are funded.

“ B-2 Funding Date ” shall mean the date, on or after the Effective Date and prior to the New Incremental Term Loan Commitment Termination Date, on which (a) all of the conditions precedent set forth in Section 6 are satisfied and (b) the Incremental Tranche B-2 Term Loans are funded.

“ Funding Dates ” shall mean the B-1 Funding Date and the B-2 Funding Date.

“ Incremental Tranche B-1 Commitment ” shall mean, with respect to each Incremental Tranche B-1 Term Lender, the commitment of such Incremental Tranche B-1 Term Lender to make Incremental Tranche B-1 Term Loans hereunder as set forth on Schedule II.

“ Incremental Tranche B-2 Commitment ” shall mean, with respect to each Incremental Tranche B-2 Term Lender, the commitment of such Incremental Tranche B-2 Term Lender to make Incremental Tranche B-2 Term Loans hereunder as set forth on Schedule III.

“ New Incremental Term Loan Commitments ” shall mean the Incremental Tranche B-1 Commitments and the Incremental Tranche B-2 Commitments.

SECTION 2.    Incremental Term Loans .  (a) On the terms and subject to the conditions set forth herein and in the Credit Agreement and in reliance upon the representations and warranties set forth herein and in the other Loan Documents, (i) each Incremental Tranche B-1 Term Lender agrees, severally and not jointly, to make, on the B-1 Funding Date, an Incremental Tranche B-1 Term Loan to the U.S. Borrower, in dollars, in an aggregate principal amount not to exceed its Incremental Tranche B-1 Commitment and (ii) each Incremental Tranche B-2 Term Lender agrees, severally and not jointly, to make, on the B-2 Funding Date, an Incremental Tranche B-2 Term Loan to the U.S. Borrower, in dollars, in an aggregate principal amount not to exceed its Incremental Tranche B-2 Commitment. Amounts paid or prepaid in respect of the New Incremental Term Loans may not be reborrowed.

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(b)        The New Incremental Term Loan Commitment of each New Incremental Term Lender shall automatically terminate upon the earlier of (i)(x) in the case of an Incremental Tranche B-1 Commitment, the making of the Incremental Tranche B-1 Term Loans on the B-1 Funding Date or (y) in the case of an Incremental Tranche B-2 Commitment, the making of the Incremental Tranche B-2 Term Loans on the B-2 Funding Date and (ii) 5:00 p.m., New York City time on the date which is 90 days after the Effective Date (the “ New Incremental Term Loan Commitment Termination Date ”).

(c)        The proceeds of the New Incremental Term Loans are to be used by the U.S. Borrower solely for the purposes set forth in Recital B of this Agreement.

SECTION 3.     Terms and Conditions .    The Incremental Tranche B-1 Term Loans and Incremental Tranche B-2 Term Loans shall constitute Specified Incremental Term Loans and Term Loans for all purposes of the Credit Agreement and the other Loan Documents, and shall have the terms that are set forth in Exhibit A-1 hereto in the case of the Incremental Tranche B-1 Term Loans and have the terms that are set forth in Exhibit A-2 hereto in the case of the Incremental Tranche B-2 Term Loans.

SECTION 4.    Representations and Warranties . To induce the other parties hereto to enter into this Agreement, each Loan Party party hereto represents and warrants to the Administrative Agent and each of the Lenders (including the New Incremental Term Lenders) that:

(a)        This Agreement has been duly authorized, executed and delivered by such Loan Party, and, constitutes a legal, valid and binding obligation of such Loan Party enforceable against such Loan Party in accordance with its terms, subject to the effects of bankruptcy, insolvency, fraudulent conveyance, moratorium and other similar laws relating to or affecting creditors’ rights generally and to general equitable principles (whether considered in a proceeding in equity or at law) and an implied covenant of good faith and fair dealing.

(b)        Each of the representations and warranties made by such Loan Party in Article III of the Credit Agreement and in each other Loan Document are true and correct in all material respects on and as of the date hereof and each Funding Date, except to the extent such representations and warranties expressly relate to an earlier date.

(c)        No Event of Default or Default has occurred and is continuing as of the Effective Date and as of each Funding Date after giving effect to the New Incremental Term Loans to be made on such Funding Date.

SECTION 5.     Effectiveness .    This Agreement shall become effective as of the date (the “ Effective Date ”) on which each of the following conditions precedent shall have been satisfied:

(a)        The Administrative Agent shall have received duly executed counterparts of this Agreement which, when taken together, bear the signatures of each Loan Party and each New Incremental Term Lender.

(b)        Each of the conditions set forth in paragraphs (b) and (c) of Section 4.01 of the Credit Agreement shall be satisfied, and the Administrative Agent shall have received a

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certificate to that effect dated as of the Effective Date and executed by a Responsible Officer of the U.S. Borrower.

(c)        As of the Effective Date, and assuming the funding in full of the New Incremental Term Loans had occurred on the Effective Date, Holdings would be in Pro Forma Compliance, and the Administrative Agent shall have received a certificate to that effect dated as of the Effective Date and executed by a Responsible Officer of the U.S. Borrower.

(d)        The Administrative Agent shall have received (i) a favorable written opinion of (x) the General Counsel or Deputy General Counsel of the U.S. Borrower and (y) Simpson Thacher & Bartlett LLP, counsel for Holdings and the U.S. Borrower, in each case addressed to the Administrative Agent, the Lenders (including the New Incremental Term Lenders) and the Issuing Banks, (ii) board resolutions and (iii) customary officer’s certificates, in each case, substantially consistent with those delivered on the Second Restatement Date. Holdings and the U.S. Borrower hereby request such counsel to deliver such opinion.

(e)        The Administrative Agent shall have received all fees and other amounts due and payable on or prior to the Effective Date, including all Upfront Fees (as defined below in Section 9) and, to the extent invoiced one Business Day prior to the Effective Date, reimbursement or payment of all reasonable out-of-pocket expenses required to be reimbursed or paid by the Borrowers hereunder or under any other Loan Document.

SECTION 6.     Conditions Precedent to Each Funding Date . The obligation of each New Incremental Term Lender to make its New Incremental Term Loans hereunder on a Funding Date shall be subject to the satisfaction, on or after the Effective Date, of the following conditions precedent:

(a)        The Administrative Agent shall have received a Borrowing Request with respect to the New Incremental Term Loans to be made on such Funding Date in accordance with Section 2.03 of the Credit Agreement.

(b)        Each of the conditions set forth in paragraphs (b) and (c) of Section 4.01 of the Credit Agreement shall be satisfied, and the Administrative Agent shall have received a certificate to that effect dated as of such Funding Date and executed by a Responsible Officer of the U.S. Borrower.

(c)        The Administrative Agent shall have received all fees and other amounts due and payable on or prior to such Funding Date, including any Ticking Fees (as defined below in Section 10) and, to the extent invoiced one Business Day prior to such Funding Date, reimbursement or payment of all out-of-pocket expenses required to be reimbursed or paid by the Borrowers hereunder or under any other Loan Document.

SECTION 7.     Acknowledgement of Guarantors . Each of the Guarantors party hereto hereby acknowledges its receipt of a copy of this Agreement and its review of the terms and conditions hereof, and each of the Guarantors hereby consents to the terms and conditions of this Agreement and the transactions contemplated hereby, and hereby affirms and confirms its guarantee of the Obligations pursuant to the Guarantee and Pledge Agreement and agrees that such guarantee shall continue to be in full force and effect and shall inure to the benefit of the

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Secured Parties, including the New Incremental Term Lenders as such in respect of their New Incremental Term Loans and the other Obligations owed to them from time to time.

SECTION 8.     Notices .      All notices hereunder shall be given in accordance with the provisions of Section 9.01 of the Credit Agreement.

SECTION 9.     Upfront Fees .     In consideration of the agreements of the New Incremental Term Lenders contained in this Agreement, Holdings and the U.S. Borrower agree to pay to the Administrative Agent, in immediately available funds, for the account of each New Incremental Term Lender, an upfront fee (the “ Upfront Fee ”), in the amounts described in Exhibit A-1 and Exhibit A-2, payable on the Effective Date . Once paid, the Upfront Fee shall not be refundable under any circumstances.

SECTION 10.  Ticking Fees .   In consideration of the agreements of the New Incremental Term Lenders contained in this Agreement, Holdings and the U.S. Borrower agree to pay to the Administrative Agent, in immediately available funds, for the account of each New Incremental Term Lender, a ticking fee (the “ Ticking Fee ”), equal to 0.25% per annum of the aggregate amount of the applicable unused New Incremental Term Loan Commitment of such New Incremental Term Lender, calculated on the basis of the actual number of days elapsed in a 360-day year, beginning to accrue on and including the 45 ^th day after the Effective Date, up to but excluding the day the applicable New Incremental Term Loan Commitment of such New Incremental Term Lender is reduced to zero or otherwise terminated in accordance with this Agreement (the “ Ticking Fee Termination Date ”), payable in arrears on the Ticking Fee Termination Date. Once paid, the Ticking Fee shall not be refundable under any circumstances.

SECTION 11.  Counterparts .    This Agreement may be executed in counterparts (and by different parties hereto on different counterparts), each of which shall constitute an original but all of which when taken together shall constitute a single contract . Delivery of an executed signature page to this Agreement by facsimile or other customary means of electronic transmission (e.g., “pdf”) shall be as effective as delivery of a manually signed counterpart of this Agreement.

SECTION 12.  APPLICABLE LAW . THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

SECTION 13.  WAIVER OF JURY TRIAL .      EACH PARTY HERETO HEREBY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF, UNDER OR IN CONNECTION WITH THIS AGREEMENT . EACH PARTY HERETO (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, AND (B) ACKNOWLEDGES THAT IT AND THE OTHER PARTIES HERETO HAVE BEEN INDUCED TO ENTER INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 13.

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SECTION 14.  Jurisdiction; Consent to Service of Process . (a) Each Loan Party hereby irrevocably and unconditionally submits, for itself and its property, to the exclusive jurisdiction of any New York State court or Federal court of the United States of America sitting in New York City, and any appellate court from any thereof, in any action or proceeding arising out of or relating to this Agreement, or for recognition or enforcement of any judgment, and each of the parties hereto hereby irrevocably and unconditionally agrees that all claims in respect of any such action or proceeding may be heard and determined in such New York State or, to the extent permitted by law, in such Federal court . Each of the parties hereto agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law . Nothing in this Agreement shall affect any right that the Administrative Agent, the Collateral Agent, any Issuing Bank or any Lender may otherwise have to bring any action or proceeding relating to this Agreement against any Loan Party or their respective properties in the courts of any jurisdiction.

(b)        Each Loan Party hereby irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection which it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Agreement in any New York State or Federal court . Each of the parties hereto hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such action or proceeding in any such court.

(c)        Each party to this Agreement irrevocably consents to service of process in the manner provided for notices in Section 9.01 of the Credit Agreement . Nothing in this Agreement will affect the right of any party to this Agreement to serve process in any other manner permitted by law.

SECTION 15.  Headings .    Headings used herein are for convenience of reference only, are not part of this Agreement and are not to affect the construction of, or to be taken into consideration in interpreting, this Agreement.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed by their respective authorized officers as of the date and year first above written.

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

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TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]

TO EXECUTE THIS AGREEMENT AS A NEW INCREMENTAL TERM LENDER:

[Signature Page to the CBRE Services, Inc. Incremental Assumption Agreement]