EXHIBIT 10.4

                [Letterhead of SAVVIS Communications Corporation]

                                                                    May 16, 2001

Reuters Holdings Switzerland SA
c/o Reuters America Inc.
The Reuters Building
Three Times Square- 20th Floor
New York, New York  10036
Attn:  Mr. David Distel

Gentlemen:

                  Reference is made to the Securities Purchase Agreement of even
date herewith (the "Securities Purchase Agreement"), by and between SAVVIS
Communications Corporation (the "Corporation") and Reuters Holdings Switzerland
SA (including its successors, assigns and affiliates, "Reuters"). Capitalized
terms used herein and not otherwise defined shall have the same meanings
ascribed to them in the Securities Purchase Agreement.

                  The Corporation agrees that, so long as Reuters is the holder
of any Notes, Conversion Shares, Purchaser Conversion Preferred or common stock
comprising or convertible into at least 5% of the outstanding voting stock of
the Corporation, Reuters shall have the right to: (i) receive notice of all
meetings of the Board of Directors of the Corporation (the "Board"), noting the
time and place of each meeting, at the same time and in the same manner as
notice is given to Directors, (ii) receive notice of all meetings of committees
of the Board, noting the time and place of each meeting, at the same time and in
the same manner as notice is given to members of such committees, (iii)
designate an observer (as may be substituted or replaced by Reuters in its sole
discretion) to attend all such meetings, in person or by telephone, and (iv)
receive all reports, consents, materials and other information distributed to
any Director of the Corporation. The Corporation shall reimburse Reuters for the
Observer's reasonable travel expenses for transportation to and from meetings of
the Board and Committees thereof. The Observer may be excused at the request of
the majority of Directors present at any such meeting for discussions of
sensitive information regarding commercial arrangements between the Corporation
and Reuters or direct competitors of Reuters. The Observer may share any
confidential information gained from presence at such meetings with the
employees, officers, directors, attorneys and advisors of Reuters, each of whom
have a need to know such information in the performance of their duties, but
such information shall otherwise be kept confidential by Reuters and its
representatives.


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                  In addition, for so long as Reuters shall hold any Notes,
Conversion Shares, Purchaser Conversion Preferred or common stock comprising or
convertible into at least 5% of the outstanding voting stock of the Corporation,
it shall have the right to nominate and elect such number of Directors of the
Corporation, but no fewer than one Director, equal to the product of the
percentage of the voting power of the Corporation held by Reuters on a
fully-diluted, as-converted basis multiplied by the number of seats on the Board
of Directors of the Corporation (rounded down to the nearest whole number).



                                      Very truly yours,

                                      SAVVIS Communications Corporation


                                      By: /s/ Steven M. Gallant
                                          --------------------------------------
                                          Name:  Steven M. Gallant
                                          Title: Vice President, General Counsel





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