Exhibit 2.1

EXECUTION VERSION

THIS TERMINATION AND RELEASE AGREEMENT (this “ Agreement ”) is made and entered into this October 24, 2006 , by and among FPL GROUP, INC. , a Florida corporation (“ FPL Group ”), CONSTELLATION ENERGY GROUP, INC. , a Maryland corporation (“ Constellation ”), and CF MERGER CORPORATION , a Florida corporation and a wholly owned subsidiary of Constellation (“ Merger Sub ” and together with FPL Group and Constellation, the “ Parties ” and each a “ Party ”).

W I T N E S S E T H:

WHEREAS, FPL Group, Constellation and Merger Sub entered into that certain Agreement and Plan of Merger, dated as of December 18, 2005 (the “ Merger Agreement ”, terms not otherwise defined herein shall have the respective meanings ascribed to them in the Merger Agreement to the extent defined therein);

WHEREAS, in connection with the negotiations surrounding the Merger Agreement, FPL Group and Constellation entered into a Confidentiality Agreement, dated as of September 6, 2005 (the “ Confidentiality Agreement ”);

WHEREAS, Constellation requested that FPL Group agree to terminate the Merger Agreement pursuant to Section 7.01(a) of the Merger Agreement, which provides that the Merger Agreement may be terminated at any time prior to the Effective Time by mutual written consent of FPL Group, Constellation and Merger Sub;

WHEREAS, FPL Group, on and subject to the terms and conditions of this Agreement, has agreed to such request by Constellation; and

WHEREAS, the boards of directors of each of FPL Group, Constellation and Merger Sub have determined to terminate the Merger Agreement and release each other from all duties, rights, claims, obligations and liabilities arising from, in connection with, or relating to, the Merger Agreement, in each case on the terms and subject to the conditions set forth herein.

NOW, THEREFORE, in consideration of the covenants and  agreements herein set forth and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the Parties agree as  follows:

1.             Termination of Merger Agreement .  Effective immediately, FPL Group, Constellation and Merger Sub hereby abandon the Merger and all other transactions contemplated by the Merger Agreement and mutually terminate the Merger Agreement pursuant to Section 7.01(a) thereof, including, notwithstanding the provisions of Section 7.02 thereof, Section 5.10 and Article VIII of the Merger Agreement, none of which provisions shall survive termination of the Merger Agreement hereunder.  Notwithstanding anything to the contrary contained in the Merger Agreement, no Released Person (as defined herein) shall have any liability or obligation under the Merger Agreement, including without limitation, as a result of any action or failure to act in connection with the Merger Agreement.

2.             Publicity; Confidentiality Agreement .  (a)  FPL Group and Constellation shall issue a joint press release in the form, and containing the contents, of Exhibit A to this

Agreement announcing the transactions contemplated by this Agreement at 8:00 a.m. (New York time) on the first Business Day immediately following the execution and delivery hereof.

(b)           The Confidentiality Agreement shall remain in full force and effect in accordance with its terms, except for Section 3 thereof, which shall be deemed terminated as of the date hereof, and except as expressly amended by the third sentence of this Section 2(b).  In addition, all information exchanged pursuant to Section 5.04(a) of the Merger Agreement shall continue to be subject to the Confidentiality Agreement.  Section 8 of the Confidentiality Agreement is hereby amended so that (i) the period of two years referenced in the third sentence of such Section 8 shall be the period of two years from the date of this Agreement and (ii) the term “Key Employee” shall mean any employee whose total annual compensation is in excess of $200,000.

3.             Fees and Expenses .  (a)  No Party shall pay a termination fee to the other Party under the Merger Agreement.  Each Party shall bear its own costs and expenses heretofore or hereafter incurred by each Party in connection with or relating to this Agreement and the Merger Agreement and the transactions contemplated hereby and thereby; provided , however , that each of FPL Group and Constellation shall bear and pay one-half of the costs and expenses incurred in connection with (y) the financial printer and SEC filing fees in connection with the Form S-4 and the Joint Proxy Statement (it being understood that if thereafter a Party is able to and does apply any such shared SEC filing fees to the fees payable in connection with a subsequent SEC filing, that Party will promptly upon the application of such fees to the subsequent filing reimburse the other Party for the amount of the SEC filing fees in connection with the Form S-4 and the Joint Proxy Statement borne by such other Party pursuant to this Section 3(a)(y)) and (z) the filing fees and economic consultant fees in connection with the premerger notification and report forms under the HSR Act and economic consultant fees in connection with the FERC application.

(b)           In the event that, on or prior to September 30, 2007, Constellation (i) consummates a Constellation Transaction (as defined below) or (ii) publicly announces its entry into a letter of intent, agreement in principle, acquisition agreement, joint venture agreement, partnership agreement or other agreement (other than a confidentiality or standstill agreement) with respect to a Constellation Transaction, then, upon the first of such events to occur, Constellation shall immediately pay FPL Group the Constellation Fee (as defined below), which shall be payable by wire transfer of immediately available funds to an account specified in writing by FPL Group for such payment.  For purposes of this Agreement, “Constellation Fee” means four hundred twenty-five million dollars ($425,000,000) if the event giving rise to Constellation’s obligation to make the payment to FPL Group occurs on or before June 30, 2007, and two hundred ten million dollars ($210,000,000) if such event occurs on or after July 1, 2007 but no later than September 30, 2007.  For purposes of this Agreement, “Constellation Transaction” means (i) any merger (including any triangular merger), consolidation, share exchange, recapitalization, liquidation, dissolution, business combination or similar transaction involving Constellation or any subsidiary of Constellation owning, operating or controlling a Constellation Material Business (as defined below) which, at consummation, results in any third party owning 35% or more of the voting securities of Constellation (or, if Constellation shall not survive as the ultimate parent company, then of the ultimate parent company resulting from such transaction) or any third party owning, directly or indirectly, 35% or more of any class of voting securities of any such subsidiary, (ii) any direct or indirect acquisition or purchase by a third party of a business or businesses (a “Constellation Material Business”) that constitutes 35% or

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more of the net revenues, net income or the assets (including equity securities) of Constellation and its subsidiaries, taken as a whole, (iii) an