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EXHIBIT 10.21

April 23, 1999

Mr. Graham Marshall
54 Eldred Street
Lexington, MA  02173

Dear Graham,

I am delighted to offer you the position of Vice President, E-Publishing
Solutions for Interleaf, Inc. Our company is at a very important juncture.
Tremendous opportunities for success are within our sights but there is work to
be done. Your credentials and energy are very impressive. I am sure that you
will have a positive influence on our results.

THE POSITION
The Vice President, E-Publishing Solutions position is one of the most important
officer level positions in our company. You will be responsible for the entire
solutions team focusing on e-Publishing, including; sales, pre-sales, marketing,
consulting and contract services. Over the next two quarters it is our intent to
increase your responsibility to also include the E-Publishing released
development team. As a direct report to the Chief Executive Officer, you will
also be asked to actively participate in the development of our overall business
strategy, interface directly with major customers as well as the Board of
Directors and participate on the senior management team.

COMPENSATION PACKAGE
The base salary for the Vice President, Solutions position is $6,154 per pay
period (26 per year), and you will participate in an annual incentive
compensation pool with total on target annual earnings of $250,000.

Your incentive compensation program is designed to reward you for meeting
quarterly and annual performance goals. The incentive compensation program will
provide you with a bonus pool of $70,000 upon achievement of mutually agreed to
revenue and profit targets, and an escalation bonus should you exceed the
target. The quarterly incentive bonus pool will be $12,500 for 100% revenue and
profit attainment; for under/over attainment the bonus payment will be made
utilizing the formula on the attached Senior Managers Incentive Plan.

In addition to your base and bonus compensation, you will receive a signing loan
of $60,000 to be utilized in the following manner:

-    $20,000 of the loan will be used for the purchase of Interleaf stock by
     yourself in the open market during your first ten (10) days of employment.
     This stock will be yours to hold and keep, but you may not sell prior to a
     liquidity event, the passage of two years or your departure from the
     company. We believe that your becoming an immediate equity holder will
     provide you a stronger leadership stance and ease communication with
     external constituents. This loan will carry an interest rate of 6% and will
     be forgiven after 18 months employment with the company.

-    The remaining $40,0000 is to be utilized to pay off your current stock
     purchase loan obligation with your current employer. The term of the loan
     will be three (3) years and carry an interest rate of 6%. Repayment will be
     made in three equal annual payments roughly 12, 24 and 36 months from your
     start date. Interleaf will forgive these loan payments as part of your
     annual compensation if you attain the following annual plan metrics:

<TABLE>
<CAPTION>

              Period       Achievement of Plan
              ------       -------------------
              <S>          <C>
              Year 1       75% of Plan = 100% of Payment Forgiven

              Year 2       75% of Plan = 70% of Payment Forgiven
                           80% of Plan = 75% of Payment Forgiven
                           90% of Plan = 85% of Payment Forgiven
                           95% of Plan = 90% of Payment Forgiven
                           100% of Plan = 100% of Payment Forgiven

</TABLE>


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<TABLE>
              <S>         <C>
              Year 3       75% of Plan = 70% of Payment Forgiven
                           80% of Plan = 75% of Payment Forgiven
                           90% of Plan = 85% of Payment Forgiven
                           95% of Plan = 90% of Payment Forgiven
                          100% of Plan = 100% of Payment Forgiven

</TABLE>


EQUITY PARTICIPATION
In addition to your signing bonus, I am delighted to offer you 60,000 stock
options. These options will be granted at the next regularly scheduled Board
meeting, with an exercise price equal to fair market value of the Common Stock
on the date of grant, vesting in four equal annual installments commencing one
year from the date of grant. As we discussed, I am fully committed to having you
achieve your long-term compensation goals.

BENEFITS PACKAGE
Your compensation will also include participate in our standard corporate
benefits program, a summary of which is attached.

I am very much looking forward to your joining our team. I know that you will do
an outstanding job in this critical role. Your expected start date is May 1,
1999. Please indicate your acceptance and agreement with the terms of this
employment offer by signing below. Again, we look forward to your joining the
team.

Sincerely,


/s/ Jaime W. Ellertson
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Jaime W. Ellertson
President and Chief Executive Officer

Accepted:

/s/ Graham Marshall
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Graham Marshall                             Date