Exhibit 99.1

CONFORMED COPY

DIRECTOR APPOINTMENT AGREEMENT

This Director Appointment Agreement, dated as of October 17, 2012 (this “Agreement”), is by and among Kensico Capital Management Corp. and the investment funds it advises (collectively, “Kensico Capital Management”) and WebMD Health Corp., a Delaware corporation (the “Company”).

WHEREAS, Thomas J. Coleman is the Co-President of Kensico Capital Management, which owns an aggregate of 5,689,488 shares of the common stock, par value $0.01 per share, of the Company (the “Common Stock”);

WHEREAS, the board of directors of the Company (the “Board”) has invited Mr. Coleman to join the Board as a director of the Company, effective as promptly as practicable after the date hereof; and

WHEREAS, the parties hereto desire to memorialize certain arrangements between Kensico Capital Management and Mr. Coleman to permit Mr. Coleman to effectively participate as a director of the Company, while continuing to fulfill his obligations to Kensico Capital Management.

NOW, THEREFORE, in consideration of and reliance upon the mutual covenants and agreements contained herein, and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties hereto agree as follows:

(i) solicit proxies or written consents of stockholders, or conduct any other type of referendum (binding or non-binding) with respect to the Voting Securities (as defined below), or from the holders of the Voting Securities, or become a “participant” (as such term is defined in Instruction 3 to Item 4 of Schedule 14A promulgated under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) in or assist any third party in any “solicitation” of any proxy, consent or other authority (as such terms are defined under the Exchange Act) to vote any shares of the Voting Securities,

(ii) actively encourage, advise or influence any other person or actively assist any third party in so encouraging, assisting or influencing any person with respect to the giving or withholding of any proxy, consent or other authority to vote or in conducting any other type of referendum with respect to the Company or the Voting Securities,

(iii) form or join in a partnership, limited partnership, syndicate or other group (other than any such group comprised solely of Kensico Capital Management), including without limitation a group as defined under Section 13(d) of the Exchange Act, with respect to the Voting Securities, or otherwise support or participate in any effort by a third party with respect to the matters set forth in clause (i) above,

(iv) present any proposal (whether pursuant to Rule 14a-8 under the Exchange Act or otherwise) for consideration for action by stockholders, make a request for a list of the Company’s stockholders, propose any nominee for election to the Board, or seek to place a representative on the Board or seek the removal of any director from the Board,

(v) grant any proxy, consent or other authority to vote with respect to any matters or deposit any of the Voting Securities held by Kensico Capital Management or its Affiliates in a voting trust or subject them to a voting agreement or other arrangement of similar effect,

(vi) make any request under Section 220 of the Delaware General Corporation Law,

(vii) threaten, file or otherwise commence or cause to be threatened, filed or otherwise commenced, any complaint, litigation, claim, action, suit, or similar proceeding (collectively, a “Legal Proceeding”) against the Company or its Affiliates, directors, officer or employees (except solely in connection with enforcing its rights hereunder),

(viii) make any public statement or statement reasonably likely to be made public regarding the Company or its Affiliates, officers, directors, employees or businesses unless approved in writing in advance by the Company,

(ix) effect, seek to effect, or in any way assist or facilitate any other person in effecting or seeking to effect (i) any tender offer or exchange offer to acquire securities of the Company, any acquisition of any material assets or business of the Company or any of its subsidiaries, or any merger, acquisition, share exchange or other business combination involving the Company or any of its subsidiaries, or (ii) any recapitalization, restructuring, liquidation, dissolution or other extraordinary transaction with respect to the Company or any of its subsidiaries or any material portion of its or their businesses,

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(x) (i) request in writing any waiver, or consent under, or any amendment of, any provision of this Agreement, or (ii) file or commence any Legal Proceeding to contest the validity of this Section 2 or to seek a release from the restrictions contained in this Section 2, or

(xi) enter into any negotiations, agreements or understandings with any person designed to accomplish the foregoing or advise, assist, encourage or seek to persuade others to take any action with respect to any of the foregoing.

As used in this Agreement: (A) the term “Affiliate” shall have the meaning set forth in Rule 12b-2 promulgated by the SEC under the Exchange Act, (B) the terms “person” or “persons” shall mean any individual, corporation (including not-for-profit), general or limited partnership, limited liability or unlimited liability company, joint venture, estate, trust, association, organization or other entity of any kind or nature (C) the term “Voting Securities” shall mean the Common Stock and any other securities of the Company entitled to vote in the election of directors, or securities convertible into, or exercisable or exchangeable for Common Stock or other securities, whether or not subject to the passage of time or other contingencies and (D) the terms “beneficial owner” and “beneficially own” shall have the meanings as set forth in Rule 13d-3 promulgated under the Exchange Act.

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IN WITNESS WHEREOF, each of the parties hereto has executed this Agreement, or caused the same to be executed by its duly authorized representative as of the date first above written.

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