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                                                                    Exhibit 10.9

                              [COGENT LETTERHEAD]


                                                            1015 31st Street, NW
                                                                       Suite 330
                                                            Washington, DC 20007
                                                              Tel: 202-965-4127-
                                                               Fax: 202-338-8798
April 3, 2000


Mr.  Scott Stewart
******

Dear Scott:

Cogent Communications ("Company") is offering Scott Stewart ("Executive") the
position of Vice President of Real Estate. Responsibilities for this position
will include building the real estate organization within the company, leading
the building access effort and general management of a team of approximately 8 -
10 individuals. The current cash compensation for this position will be a base
salary of $145,000 and $45,000 payable as a bonus based upon mutually agreeable
performance targets both corporate and individual. Base salary will be paid
semi-monthly. Due to the early stage nature of Cogent's business plan, your
initial year 2000 performance targets have been deemed met and a bonus of
$29,970 (prorated for year 2000) will be payable on a quarterly basis for the
rest of the year 2000. The next year's bonus payment structure will be
determined at a later date. Upon over achievements of targets and milestones,
there will be a loading factor applied to the compensation with a structure as
follows: 60% based on personal achievement, 20% based on organization
achievement, and 20% based on company achievement.

In addition to the cash compensation you receive, Cogent will issue 185,000
shares of options to purchase common equity in the company at a strike price of
$.25. 100% of these options will vest straight line on a quarterly basis over a
4 year period. Vesting will begin on your start date of April 4th, 2000. Based
upon the targeted capitalization of the company, there will be approximately up
to 49.5 million shares outstanding.

Cogent will periodically perform employee evaluations at minimum intervals of 12
months commencing within 18 months of your employment. These reviews will be
utilized to evaluate your compensation package relative to the market for
similar level professionals at organizations of comparable stage of development
and market opportunity to Cogent. The findings of these reviews will be
submitted to the company's compensation committee for final decision and
appropriate compensation adjustments.

In the event of Constructive Termination Without Cause, Termination Without
Cause, Change in Control, or Potential Change in Control, Executive will receive
9 month's salary against $145,000, nine months of benefits coverage, all vested
shares and shares to be vested in the quarter of termination. In the event of a
Change of Control or Potential Change in Control and


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either Termination Without Cause or Constructive Termination, in addition to
the above mentioned conditions, Executive will receive 50% of your unvested
shares at the $.25 strike price.

For purposes of this Agreement, the term "Cause" means (i) the willful and
continued failure by the Executive to substantially perform the Executive's
duties with the Company after written notification by the Company, (ii) the
willful engaging by the Executive in conduct which is demonstrably injurious to
the Company, monetarily or otherwise, or (iii) the engaging by the Executive in
egregious misconduct involving serious moral turpitude. For purposes of this
Agreement, no act, or failure to act, on the Executive's part shall be deemed
"willful" unless done, or omitted to be done, by the Executive not in good faith
and without reasonable belief that such action was in the best interest of the
Company.

For the purposes of this Agreement, a "Change in Control" shall be deemed to
occur if (i) the stockholders of the Company approve a definitive agreement to
merge the Company into or consolidate the Company with another entity, sell or
otherwise dispose of all or substantially all of its assets or adopt a plan of
liquidation, (ii) the "beneficial ownership" (as defined in Rule l3d-3 under the
Exchange Act) of securities representing 50% or more of the combined voting
power of the Company is acquired, other than from the Company, by any "person"
as defined in Sections 13(d) and 14(d) of the Exchange Act, or (iii) at any time
during any period of two consecutive years, individuals who at the beginning of
such period were members of the Board of Directors of the Company cease for any
reason to constitute at least a majority thereof.

For the purposes of this Agreement, a "Potential Change in Control" shall be
deemed to occur if (i) a tender offer is made for the stock of the Company
representing 50% or more of the total voting power of the Company's stock; (ii)
any person makes a solicitation of proxies for the election of directors who
have not been recommended by the Company; (iii) the Company enters into
negotiations with respect to a transaction which would upon consummation
constitute a Change in Control; or (iv) the Board adopts a resolution to the
effect that, for the purposes of this Agreement, a Potential Change in Control
has occurred.

The relocation by the Company of the Executive's office to a location more than
50 miles from the Company's present office shall constitute an event of
Termination without Cause, Constructive Termination without Cause or a Change in
Control.

In order to compensate you for moving expenses associated with this position,
Cogent proposes a $40,000 moving budget with a commitment on your part to
relocate your principal residence to the company's headquarter location in
Washington, DC within 9 months. During the intervening period, you are committed
to spending 5 days per week at the company's headquarters or on company related
travel and bearing all non-company related travel and lodging expenses
associated with that commitment from the above mentioned budget.

As a member of the Cogent team, you will be entitled to company funded health
care insurance, dental coverage, and life insurance. The company will also
implement a 401k retirement plan that will be corporately administered, however,
it will require individual contributions on a non-matching basis by individual
participants. Cogent is prepared to offer 3 weeks of paid


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vacation. Additionally, the company will implement 6 fixed major holidays and
there will be 1 discretionary floating holiday to be chosen from other less
recognized holidays.

Upon acceptance of this offer of employment, you will be required to sign a
non-compete and non-disclosure agreement with the company.

We understand there may be some transition time while you wrap up your current
project.

If this offer is accepted by April 3rd, 2000, your effective employment date
will be considered April 4th, 2000 and your vesting will begin at that time.
During the period of time between April 4th, 2000 and April 28, 2000, your
duties and responsibilities will be from your current location. Your
availability will be on an as-needed telephonic basis and during this period of
employment, your sole compensation will be the accrued vesting of your options.
The cash portion of your compensation will commence upon your full time
employment in Washington, DC on or about April 28th, 2000.

We look forward to having you join our team and build the most advanced next
generation network for high speed Internet services, This offer remains in
effect through April 28, 2000 at 2:00 pm. If you have any further questions,
please give me a call at 202-338-4067.

Sincerely,


Dave Schaeffer


Agreed and Accepted


         /s/
-------------------------

Scott Stewart