AMENDMENT NO. 1 TO JOINT VENTURE AGREEMENT

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Exhibit 10.1

AMENDMENT NO. 1 TO JOINT VENTURE AGREEMENT

        This Amendment No. 1 to Joint Venture Agreement (" Amendment No. 1 ") amends the Joint Venture Agreement, dated as of December 20, 2007, by and among Molson Coors Brewing Company, Coors Brewing Company, SABMiller plc, Miller Brewing Company and (upon its execution of a joinder to the Joint Venture Agreement) MillerCoors LLC (the " Joint Venture Agreement "). Terms used herein and not otherwise defined herein have the meanings set forth in the Joint Venture Agreement.

        The parties hereby agree to amend the Joint Venture Agreement as follows:

1.

Section 1.01(b) of the Joint Venture Agreement is amended by adding the following reference:

"Interim Operating Agreement 2.02"

2.

Section 2.01 of the Joint Venture Agreement is hereby amended to read in its entirety as follows:

" Organization of the Company . On or prior to the Closing Date, the Shareholders shall cause the Company to be formed as a Delaware limited liability company by filing a certificate of formation with the Secretary of State of the State of Delaware in the form agreed by the Shareholders and by their execution of the Interim Operating Agreement. After the formation of the Company and on or prior to the Closing Date, the Shareholders shall cause the Company to execute a joinder to this Agreement as a Party hereto in the form agreed by the Shareholders (the " Joinder ")."

3.

Section 2.02 of the Joint Venture Agreement is hereby amended to read in its entirety as follows:

" Operating Agreement . Concurrently with the formation of the Company, the Shareholders shall execute and deliver a limited liability company operating agreement to be agreed upon by the Shareholders and which shall govern the affairs of the Company and the conduct of the Company's business until such agreement is replaced by the Operating Agreement on the Closing Date (the " Interim Operating Agreement "). On the Closing Date, the Shareholders shall execute and deliver the amended and restated limited liability company operating agreement governing the affairs of the Company and the conduct of the Company's business substantially in the form attached hereto as Attachment I (the " Operating Agreement ")."

4.

Section 2.04 of the Joint Venture Agreement is hereby amended to read in its entirety as follows:

" Shareholders . Upon the formation of the Company, the Company shall have authorized capital consisting of 1,000,000 Shares, consisting of 840,000 Class A Shares and 160,000 Class B Shares, and no preferred shares. Upon the formation of the Com