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                                                                   EXHIBIT 10.21


                               AMENDMENT NO. 1 TO
                              EMPLOYMENT AGREEMENT


         This Amendment No. 1 dated as of July 27, 2000 amends the Employment
Agreement dated September 28, 1998 by and between R.H. Donnelley Corporation, a
Delaware corporation (the "Company"), and Phillip C. Danford (the "Executive")
(the "Existing Agreement", and as amended, the "Agreement").

         WHEREAS, the Company considers it essential and in the best interests
of its shareholders to foster the continued employment of its senior management
personnel, and the Executive is an important member of the Company's senior
management; and

         WHEREAS, the Company wishes to clarify its intent with respect to
benefits to be provided to the Executive in certain events following a Change in
Control.

         NOW, THEREFORE, the parties agree that the Existing Agreement is hereby
amended as follows:

         1. Paragraph 1 of the Existing Agreement is amended by inserting the
following sentence at the end thereof:

            "Notwithstanding the foregoing, no person (including the Company and
            any successor thereto) shall be permitted to give notice of such
            intention within two years following a Change in Control, as
            hereinafter defined."

         2. Paragraph 8 of the Existing Agreement is amended by deleting the
last sentence thereof and replacing such sentence with the following:

            "The provisions of this Section 8 (and any related provisions of
            Section 10) shall survive any non-renewal of this Agreement by the
            Company pursuant to Section 1."

         3. Subsection (c) of Paragraph 8 of the Existing Agreement is amended
by deleting ", as hereinafter defined," from the first sentence thereof.

         4. This Amendment No. 1 shall be conditioned upon the receipt by each
party hereto from the other a counterpart hereof signed by such other party or
facsimile or other written confirmation that such other party has signed a
counterpart hereof.

         5. This Amendment No. 1 shall be governed by and construed in
accordance with the laws of the State of New York.

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         6. This Amendment No. 1 may be signed in counterparts, each of which
shall be an original, with the same effect as if the signatures thereto and
hereto were upon the same instrument.

         IN WITNESS WHEREOF, the parties have duly executed this Amendment No. 1
as of the day and year first above written.


                                             Phillip C. Danford

                                            /s/ Phillip C. Danford
                                            ----------------------


                                            R.H. DONNELLEY CORPORATION


                                            By: /s/ Judith A. Norton
                                               ----------------------
                                                Judith A. Norton
                                                SVP, Human Resources


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