Healthspring S-3ASR Automatic shelf registration

Exhibit 5.1

150 Third Avenue South, Suite 2800
Nashville, TN 37201
(615) 742-6200

March 24, 2011

HealthSpring, Inc.
9009 Carothers Parkway, Suite 501
Franklin, Tennessee 37067

     Re:     Shelf Registration Statement of HealthSpring, Inc. (the “Company”)

Ladies and Gentlemen:

     We have acted as counsel to the Company in connection with its filing of an automatic shelf Registration Statement on Form S-3 (the “Registration Statement”) with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), for the purpose of registering with the Commission common stock, par value $0.01 per share, of the Company (the “Common Stock”). The Common Stock may be issued in an unspecified number, at prices and on terms to be set forth in one or more prospectus supplements (each a “Prospectus Supplement”) to the prospectus contained in the Registration Statement.

     In connection with this opinion, we have examined signed copies of the Registration Statement as filed with the Commission, including the exhibits thereto. We have also examined and relied upon the minutes of meetings of the stockholders and the Board of Directors of the Company as provided to us by the Company, the Certificate of Incorporation and Bylaws of the Company, each as restated and/or amended to date, and such other documents, records, certificates and other instruments as we have deemed necessary for purposes of rendering the opinions hereinafter set forth.

     In our examination of the foregoing documents, we have assumed that all documents we have received are the valid and binding obligations of and enforceable against the parties thereto. We have also assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as copies, the authenticity of the originals of such latter documents and the legal competence of all signatories to such documents. We have also relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinions set forth below, on certificates of officers of the Company.

     The opinions expressed below are limited to the state law of Tennessee, the General Corporation Law of the State of Delaware (which include applicable provisions of the Delaware

HealthSpring, Inc.
March 24, 2011
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Constitution and reported judicial decisions interpreting the Delaware General Corporation Law and the Delaware Constitution) and the federal laws of the United States of America. Without limiting the generality of the foregoing, we express no opinion with respect to (i) state securities or “blue sky” laws, or (ii) state or federal antitrust laws.

     Based upon and subject to the foregoing and subject to the assumptions, limitations and qualifications set forth herein, we are of the opinion that when (i) specifically authorized for issuance by the Company’s Board of Directors or an authorized committee thereof (the “Stock Authorizing Resolutions”), (ii) the Registration Statement has become effective under the Securities Act, (iii) the terms of the sale of the Common Stock have been duly established in conformity with the Company’s Certificate of Incorporation and Bylaws, each as restated and/or amended to date, and do not violate any applicable law or result in a default under or breach of any agreement or instrument binding on the Company and comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company, (iv) the Common Stock has been issued and sold as contemplated by the Registration Statement and a Prospectus Supplement and (v) the Company has received the consideration provided for in the Stock Authorizing Resolutions and such consideration per share is not less than the par value per share of the Common Stock, then the Common Stock will be validly issued, fully paid and non-assessable.

     It is understood that this opinion is to be used only in connection with the offer and sale of the Common Stock while the Registration Statement is in effect.

     Please note that we are opining only as to the matters expressly set forth herein, and no opinion should be inferred or implied as to any other matters or beyond that expressly stated herein. This opinion is based upon currently existing statutes, rules, regulations and judicial decisions, and we disclaim any obligation to advise you of any change in any of these sources of law or subsequent legal or factual developments which might affect any matters or opinions set forth herein.

     We hereby consent to the filing of this opinion with the Commission as an exhibit to the Registration Statement in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of our name therein and in the related prospectus and any Prospectus Supplement under the caption “Legal Matters.” In giving such consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission.

Very truly yours,

/s/ Bass, Berry & Sims PLC