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                                                                    Exhibit 10.6


[INTERMEDIA COMMUNICATIONS LOGO]



December 1, 1999

Robert M. Manning
3625 Queen Palm Drive
Tampa, FL 33619

Dear Rob:

This letter will amend the compensation terms of your employment by the Company
as follows:

If your employment with the Company is terminated by the Company for any reason
other than for cause (described below), the Company will continue to pay your
base salary as in effect at the time of termination through the later of March
31, 2001 or one year following the date of termination, payable (i) for the
first six months following such termination on the same dates it would have
been paid had your employment continued through such later date, with the
remainder paid in a lump sum at the conclusion of the initial six months, or
(ii) if your termination occurred following the occurrence of a Change of
Control (defined below), in a lump sum promptly following such termination.
Your entitlement to receive payments pursuant to clause (i) of the preceding
sentence shall terminate and cease to be of any force or effect in the event
you, directly or indirectly (whether by an entity of which you own greater than
10% of the outstanding equity interest or by which you are employed in a senior
executive capacity) or otherwise knowingly hire within six months following
your date of termination any employee of the Company who was employed by the
Company or its subsidiaries on the date of your termination.

Cause means (i) any conduct or behavior by you that would reasonably be
expected to have a material adverse affect on the Company's business or
reputation, (ii) commission by you of an act involving moral turpitude or
dishonesty, including fraud, (iii) your material failure to reasonably perform
your duties for the Company, or (iv) your willful failure to perform or abide
by any lawful directions or instructions of the Company consistent with your
capacity as a senior executive of the Company.

In addition, and without limitation of any payments to be made to you pursuant
to the preceding paragraph, upon occurrence of a Change of Control of the
Company, the Company shall pay to you, in a lump sum promptly following the
occurrence of such a Change of Control, an amount equal to two multiplied by
the sum of your base salary in effect immediately prior to the occurrence of
such Change of Control, plus two multiplied by the amount of the target bonus
applicable to the position held by you immediately prior to the occurrence of
such Change of Control for the fiscal year of the Company in which the Change
of Control occurs.
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For purposes of the preceding sentence, "Change of Control" means the sale,
exchange or transfer of common stock of the Company, whether in one transaction
or a series of related transactions occurring in one year, which results in an
accumulation of 50% or more of the outstanding shares of common stock (on a
fully diluted basis) in one holder or several affiliated holders (or any such
transaction(s) occurring within six months that results in an accumulation of at
least 35% of such shares of common stock (on a fully diluted basis).
Notwithstanding anything in this letter to the contrary, if it shall be
determined that any payment or distribution by the Company to you or for your
benefit (whether paid or payable or distributed or distributable pursuant to the
terms of this letter or otherwise) (a "Payment") would constitute an "excess
parachute payment" within the meaning of Section 49999 of the internal revenue
code, then the Payments, in the aggregate, shall be reduced (in a manner
elected by you, or the Company if you fail to make such an election) to the
greatest amount that could be paid to you so that no portion thereof shall be
subject to the excise taxes imposed by Section 4999 of the internal revenue
code.

Expected as amended hereby, the terms of your original offer letter continue in
full force and effect. If the foregoing is acceptable to you, please sign in the
space provided below and return to me one fully executed copy of this letter.
Nothing in this letter will be deemed to affect the at-will status of your
continued employment by Intermedia.


                                             Intermedia Communications Inc.

                                             /s/ David C. Ruberg
                                             ------------------------------
                                             David C. Ruberg
                                             President and CEO


Agreement with terms
of letter confirmed:

/s/ Robert M. Manning
-----------------------
Robert M. Manning