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                                                                    Exhibit 10.4





August 22, 2001

(Via Federal Express)

Mr. James D. Taiclet, Jr.
5049 E. Cannon Drive
Paradise Valley, AZ 85253

Dear Jim:

I am pleased to offer you the position of President and Chief Operating Officer
of American Tower Corporation. You will be reporting to me, and I have every
confidence that your leadership will make a real difference. I very much
appreciate the time and effort you invested in the search process. The following
outlines the terms of the offer:

o    Salary

     Your starting annual cash compensation will be $500,000, paid semi-monthly,
     increasing to $550,000 as of January 1, 2002. Thereafter, you will receive
     annual increases beginning January 1, 2003 as recommended by me to the
     Compensation Committee.

o    Stock Options

     You will be granted 500,000 options on your start date of September 3,
     2001, or at any time during your first 30 days of employment. The strike
     price will be consistent with the date on which the actual grant occurs.
     For the following three years, beginning in 2002, you will receive
     additional annual option grants of 175,000 shares to be issued in the
     fourth quarter of the year. All options will be granted at the market value
     on the date of issuance with our standard four-year vesting at the rate of
     25% per year. (See attached stock option plan for additional details.) You
     would receive 100% vesting under any of the following three circumstances:

     (1)  if American Tower were to have a change of control (meaning someone
          other than present management and directors acquired majority voting
          control),

     (2)  if I should cease to be Chief Executive Officer (other than by reason
          of death or disability), and you are not selected to succeed me as
          Chief Executive Officer, or

     (3)  if you are not selected to succeed me as CEO within a period of three
          years.

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Mr. James D. Taiclet, Jr.
August 22, 2001
Page 2

o    Severance

     In the unlikely event that you were asked to leave the company for other
     than cause (which will be defined as theft, fraud, or any other type of
     egregiously poor behavior), you will be paid a severance benefit of 12
     months base salary continuance plus continuance of benefits for the 12
     month period. This severance clause also applies if you voluntarily choose
     to leave the company after being asked to assume a position of lesser
     responsibility than President and COO or if you choose to leave the company
     as a result of the occurrence of any items (1) or (2) in the preceding
     paragraph.

o    Automobile

     The company will provide an allowance of up to $1,000 per month for a car
     of your choosing. You will also be eligible for reserved parking in our
     building.

o    Moving Expenses

     American Tower will reimburse up to $100,000 in moving related costs,
     including sales commissions.

o    Benefits

     You will be entitled to all American Tower executive benefits. A listing of
     benefits and appropriate information are enclosed.

o    Vacation

     Four weeks per year (more if you need it).

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Mr. James D. Taiclet, Jr.
August 22, 2001
Page 3

If our offer is acceptable, please sign and return a copy of this letter for our
files.

I look forward to partnering with you, Jim, as we build American Tower into an
exciting company that is highly regarded by its customers, shareholders, and
employees. Together, and with the help of other key team members, I think we can
get a lot of good things done and have some fun along the way.

Warm regards,

/s/ Steven B. Dodge

Steven B.  Dodge
Chairman and
Chief Executive Officer

Accepted,

 /s/ James D. Taiclet, Jr.
--------------------------------------------
     James D. Taiclet, Jr.


Enclosure