Exhibit 23.1



Consent of Independent Registered Public Accounting Firm



We consent to the incorporation by reference in the following Registration Statements:



| |  |  | Form S-8 No. 333-114100 pertaining to the Caremark Rx, Inc. 2004 Incentive Stock Plan;
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| |  |  | Form S-4 No. 333-109519 pertaining to CaremarkRx, Incs merger with AdvancePCS;
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| |  |  | Form S-8 No. 33-86806 pertaining to the 1993 Stock Option Plan;
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| |  |  | Form S-8 No. 333-11875 pertaining to the MedPartners Incentive Compensation Plan;
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| |  |  | Form S-8 No. 333-11127 pertaining to the MedPartners/Mullikin, Inc. 1995 Stock Option Plan;
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| |  |  | Form S-8 No. 333-05703 pertaining to the MedPartners, Inc. & Subsidiaries Employee Retirement Savings Plan;
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| |  |  | Form S-8 No. 333-14159 pertaining to the Caremark International Inc. 401 Care Retirement Savings Plan;
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| |  |  | Form S-8 No. 333-14163 pertaining to the Caremark International Inc. 1992 Stock Option Plan for Non-Employee Directors and the Caremark International Inc.
Qualified and Employee Stock Purchase Plan;
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| |  |  | Form S-8 No. 333-38835 pertaining to the MedPartners, Inc. 1997 Long Term Incentive Compensation Plan;
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| |  |  | Form S-8 No. 333-16863 pertaining to the MedPartners, Inc. Employee Stock Purchase Plan;
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| |  |  | Form S-3 No. 333-17339 pertaining to the resale of common stock by certain selling shareholders;
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| |  |  | Form S-8 No. 333-30145 pertaining to the MedPartners, Inc. 1994 Non-Employee Director Stock Option Plan and 1994 Stock Incentive Plan;
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| |  |  | Form S-8 No. 333-42967 pertaining to the Amended and Restated MedPartners, Inc. 1995 Stock Option Plan;
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| |  |  | Form S-8 No. 333-50849 pertaining to the MedPartners, Inc. 1997 Long Term Incentive Compensation Plan;
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| |  |  | Form S-3 No. 333-53761 pertaining to the resale of common stock by certain selling shareholders;
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| |  |  | Form S-8 No. 333-64371 pertaining to the MedPartners, Inc. 1998 Employee Stock Option Plan;
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| |  |  | Form S-8 No. 333-68709 pertaining to the Non-Qualified Stock Option Agreement Dated August 6, 1998 between MedPartners, Inc. and Edwin M. Crawford;
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| |  |  | Form S-8 No. 333-68707 pertaining to the MedPartners, Inc. 1998 New Employee Stock Option Plan; and
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| |  |  | Form S-4 No. 333-139470 of CVS Corporation pertaining to the proposed merger of CVS Corporation and Caremark Rx, Inc.
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of our reports dated February 24, 2007, with respect to the consolidated financial
statements and schedule of Caremark Rx, Inc.; Caremark Rx, Inc. managements assessment of the effectiveness of internal control over financial reporting as of December 31, 2006; and the effectiveness of internal control over financial
reporting as of December 31, 2006, included in this Annual Report on Form 10-K for the year ended December 31, 2006.



/s/    Ernst & Young LLP



Nashville, Tennessee

February 24, 2007