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                                                               Exhibit 10(c)(vi)

                              EMPLOYMENT AGREEMENT

This Agreement is made as of September 1, 1999 by and between American Science &
Engineering, Inc. (the "Company"), a Massachusetts corporation having its
principal place of business in Billerica, Massachusetts, and Ralph G. Foose,
(the "Executive").

The Company desires to retain the services of the Executive, and the Executive
is willing to render such services, in accordance with the terms hereinafter set
forth.

Accordingly, the Company and the Executive agree as follows:

1. The Company agrees to hire the Executive as, and the Executive agrees to
accept and perform the duties of, Vice President, Operations of the Company.
Management will recommend to the Board of Directors of the Company that the
Executive be elected to the position at the next meeting of the Board.

2. The Executive's initial salary shall be Two Hundred Thousand Dollars
($200,000) per annum ("Base Pay") payable not less frequently than monthly in
accordance with standard company policy for executives. The Executive shall also
be entitled to an annual bonus in an amount of up to 50% of Base Pay based on
Executive's performance, as determined by the CEO, on specific goals to be
agreed to between Executive and the Company's CEO. Base Pay shall be reviewed
annually and may be increased at the discretion of the CEO. Executive shall also
be granted options to purchase 50,000 shares of the Company's Common Stock at a
price equal to the closing price on the date of this Agreement. The options will
vest over three (3) years and will be otherwise subject to all of the terms and
conditions of the Company's 1999 Combination Stock Options Plan, including
approval of the grant by the Board of Directors at its next meeting and approval
of the Stock Option Plan by the stockholders at their next meeting.

3. (a) The Company shall pay to the Executive the "Severance Payment" in the
event that the Executive is terminated by the Company within sixty (60) days
prior to or twelve (12) months after the occurrence of a "Change of Control," as
defined below. The Severance Payment shall be made at the time of such
termination.

      (b) The "Severance Payment" shall be a one-time payment equal to the
higher of: (i) the annual rate of the Executive's base salary in effect one
month prior to the occurrence of the Change of Control, or (ii) the annual rate
of the Executive's base salary in effect at the time of such termination. The
Severance Payment shall also include the continuation of all benefits received
by the Executive prior to termination for a period equal to the lesser of one
year or the start of new employment by the Executive in which he receives
substantially similar benefits.

      (c) A "Change of Control" shall be deemed to have occurred if:

      (i) any person (as defined in Section 13 (d) or 14 (d)(2) of the
      Securities Exchange Act of 1934) shall have become the beneficial owner of
      50 percent or more of the combined voting power of the Company's voting
      securities;

      (ii) the Continuing Directors shall have ceased for any reason to
      constitute a majority of the Board of Directors of the Company. For this
      purpose, a "Continuing Director" shall include members of the Board of
      Directors of the Company as of the date of this
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      Agreement and any person nominated for election to the Board of Directors
      of the Company by a vote of the majority of the then Continuing Directors;

      (iii) the stockholders approve the complete liquidation or dissolution of
      the Company, or

      (iv) the stockholders approve by the requisite vote any of the following
      transactions: (A) a merger or consolidation of the Company (except for a
      merger in respect of which no vote of the stockholders of the Company is
      required); (B) a sale, lease, exchange, mortgage, pledge, transfer or
      other disposition (in one transaction or a series of transactions),
      whether as part of a dissolution or otherwise, of assets of the Company or
      of any direct or indirect majority-owned subsidiary or the Company (other
      than to any direct or indirect wholly-owned subsidiary or to the Company)
      having an aggregate market value equal to 50% or more of either the
      aggregate market value of all of the assets of the Company determined on a
      consolidated basis or the aggregate market value of all the outstanding
      stock of the Company immediately prior tot he transaction; or (C) a tender
      or exchange offer for 50% or more of the outstanding voting stock of the
      Company.

4. (a) If the Executive is terminated for any reason other than (i) Cause (as
defined below); or (ii) pursuant to Paragraph 3 ("Termination for Convenience")
the Executive shall receive an amount equal to the greater of the amount that
would be due under the Company's then-current severance policy, if any, or six
months of his then-current Base Pay, payable, at the Company's option, on the
last date of his employment or in weekly installments. In case of Termination
for Convenience, the Executive shall be entitled to a continuation of all
benefits being received by him at the time of termination for the lesser of six
(6) months from the date of termination, or until the date in which the
Executive begins new employment in which he receives substantially similar
benefits. If the Executive is Terminated for Convenience within twelve (12)
months of a change in the Company's President/CEO, the Executive shall be
entitled to receive the Severance Payment described in Paragraph 3(b) in place
of the benefits described in this Paragraph 4.

      (b) For the purposes of this Agreement, "Cause" shall mean: (i) the
determination by the President of the Company, in agreement with the Board of
Directors, that the Executive has willfully failed to perform his duties in the
course of his employment under this Agreement consistent with those of a Vice
President, Operations as expressly instructed by the President/CEO; or (ii) the
final conviction of the Executive for, or his plea of nolo contendere to, a
felony or any other crime which involves fraud, dishonesty or moral turpitude.

5. The Company may not assign all or any part of its obligations under this
Agreement, except to a successor as provided for in this paragraph. The Company
will require any successor (whether direct or indirect, by purchase, merger,
consolidation or otherwise) to all or substantially all of the business or
assets of the Company expressly to assume and agree to perform this Agreement to
the same extent that the Company would be required to perform it if no
succession had taken place. As used in this Agreement, unless the context
requires otherwise, the "Company" shall mean the Company as defined above or any
successor to its business or assets as aforesaid which assumes and agrees to
perform this Agreement, by operation of law, or otherwise. This Agreement shall
inure to the benefit of and be enforceable by and binding upon (i) any such
successor and (ii) the Executive's personal or legal representatives, executors,
administrators and designated beneficiaries.
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6. This Agreement contains the entire agreement between the parties with respect
to the subject mater hereof and supersedes all prior oral and written
agreements, understandings and commitments between the parties relating to this
Agreement. Notwithstanding the foregoing, the Executive shall at all times
remain subject to all policies and procedures of the Company that relate to
employees of the Company, except to the extent that this Agreement contains
terms or provisions that are contrary to or provides greater benefits than such
policies and procedures, in which case this Agreement shall control. No
amendment to this Agreement shall be made except by a written instrument signed
by both parties.

7. The Executive shall be entitled to reimbursement or payment of relocation
expenses as agreed between Executive and the CEO.

8. This Agreement shall be construed and enforced under and be governed in all
respects by the law of The Commonwealth of Massachusetts, without regard to the
conflict of law principles thereof.

IN WITNESS WHEREOF, the Company has caused this instrument to be executed on its
behalf by a duly authorized officer and the Executive has executed this
instrument, all as of the date set forth above.


                               AMERICAN SCIENCE & ENGINEERING, INC.


                               By: /s/ Ralph S. Sheridan
                                   -------------------------------------
                                   Ralph S. Sheridan, CEO and President


                                   /s/ Ralph G. Foose
                                   -------------------------------------
                                   Ralph G. Foose