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                                                                    Exhibit 5.1
                         [ALSTON & BIRD LLP LETTERHEAD]

                              One Atlantic Center
                           1201 West Peachtree Street
                          Atlanta, Georgia 30309-3424

                                  404-881-7000
                               Fax: 404-881-4777
                                 www.alston.com


                                November 9, 2000

WebMD Corporation
400 The Lenox Building
3399 Peachtree Road NE
Atlanta, Georgia 30326

         Re:      Form S-3 Registration Statement -- WebMD Corporation

Ladies and Gentlemen:

         We have acted as counsel for WebMD Corporation, a Delaware
corporation (the "Company"), in connection with the referenced Registration
Statement on Form S-3 (the "Registration Statement") being filed by the
Company with the Securities and Exchange Commission (the "Commission")
under the Securities Act of 1933, as amended, and covering 15,000,000 shares
of the Company's common stock, par value $0.0001 per share ("Common
Stock"), that may be sold by the selling stockholders as contemplated by the
prospectus included therewith. This Opinion Letter is rendered pursuant to Item
16 of Form S-3 and Item 601(b)(5) of Regulation S-K.

         We have examined the Amended and Restated Certificate of Incorporation
of the Company, as amended, the Bylaws of the Company, as amended, records of
proceedings of the Board of Directors of the Company deemed by us to be
relevant to this opinion letter, the Registration Statement and other
agreements or documents we deemed necessary for the purpose of expressing the
opinions set forth herein. We also have made such further legal and factual
examinations and investigations as we deemed necessary for purposes of
expressing the opinion set forth herein.

         As to certain factual matters relevant to this opinion letter, we have
relied upon certificates and statements of officers of the Company and
certificates of public officials. Except to the extent expressly set forth
herein, we have made no independent investigations with regard thereto, and,
accordingly, we do not express any opinion as to matters that might have been
disclosed by independent verification.

         Our opinion set forth below is limited to the General Corporation Law
of the State of Delaware and reported judicial decisions interpreting such
General Corporation Law, and we do not express any opinion herein concerning
any other laws.

         This opinion letter is provided to the Company and the Commission for
their use solely in connection with the transactions contemplated by the
Registration Statement and may not be used, circulated, quoted or otherwise
relied upon by any other person or for any other purpose without our express
written consent. The only opinion rendered by us consists of those matters set
forth in the following paragraph, and no opinion may be implied or inferred
beyond the opinion expressly stated. The opinion rendered herein is as of the
date hereof, and we make no undertaking and expressly disclaim any duty to
supplement such opinion if, after the date hereof, facts and circumstances come
to our attention or changes in the law occur which could affect such opinion.

         Based upon the foregoing, it is our opinion that the 15,000,000
shares of Common Stock covered by the Registration Statement when sold will
be validly issued, fully paid and nonassessable.

         We consent to the filing of this opinion letter as an exhibit to the
Registration Statement and to the use of our name under the heading "Legal
Matters" in the Prospectus constituting a part thereof.





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                                   Sincerely,

                                   ALSTON & BIRD LLP


                                   By: /s/ C. Mark Kelly
                                      -----------------------------------
                                      A Partner