8-K

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U.S. SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

Current Report Pursuant
to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) May 20, 2003

AMERICAN SCIENCE AND ENGINEERING, INC.
(Exact Name Of Registrant As Specified In Its Charter)

MASSACHUSETTS
(State or Other Jurisdiction of Incorporation)

1-6549	04-2240991
(Commission File Number)	(I.R.S. Employer Identification No.)
829 MIDDLESEX TURNPIKE, BILLERICA, MASSACHUSETTS	01821
(Address of Principal Executive Offices)	(Zip Code)

(978) 262-8700
(Registrant's Telephone Number, Including Area Code)

N/A
(Former Name or Former Address, if Changed Since Last Report)

ITEM 5. OTHER EVENTS

        On May 20, 2003, American Science and Engineering, Inc. announced that the Company's Board of Directors had replaced Ralph S. Sheridan as President and Chief Executive Officer. A copy of the press release issued on May 20, 2003 regarding the replacement of Mr. Sheridan is filed as Exhibit 99.1.

ITEM 7. EXHIBITS

Exhibit Number	Description
99.1	Press Release dated May 20, 2003

SIGNATURE

        Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Date: May 20, 2003	AMERICAN SCIENCE AND ENGINEERING, INC.
	By:	/s/  PAUL THEODORE OWENS Paul Theodore Owens Vice President, Treasurer and Chief Financial Officer

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EXHIBIT INDEX

Exhibit No.	Description
99.1	Press Release of the Company dated May 20, 2003, announcing replacement of Mr. Ralph S. Sheridan as President and Chief Executive Officer.

4

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SIGNATURE
EXHIBIT INDEX

EX-99.1

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EXHIBIT 99.1

FOR IMMEDIATE RELEASE

American Science and Engineering, Inc. Names Dr. Roger Heinisch Interim CEO

Board Replaces CEO and President, Ralph Sheridan

BILLERICA, Mass.—May 20, 2003—American Science and Engineering, Inc. (AMEX:ASE) announced today that its board of directors has replaced the Company's CEO and President, Ralph Sheridan. The board has named a director of the Company, Dr. Roger P. Heinisch, to serve as interim President and CEO, pending appointment of a permanent successor to Mr. Sheridan.

General William Odom, Chairman of American Science and Engineering's (AS&E®)'s board of directors, stated that "In the nearly ten years in which Ralph served as AS&E's CEO he provided excellent leadership, first in turning around its operations and then in putting it on the path to significant revenue growth." General Odom said that the board had decided that the Company needs different leadership to take it into the future.

Dr. Heinisch has been a director of AS&E since 1999. He served for many years with Honeywell and Alliant Techsystems as a top executive in scientific and management positions. Dr. Heinisch is also a former member of the Army Science Board and an advisor to the Defense Science Board.

General Odom indicated that the Company's board expected to initiate a search for a permanent successor to Mr. Sheridan in the near future.

About AS&E®

AS&E develops and manufactures sophisticated X-ray inspection products for critical detection and security applications. These systems are solving an expanding range of inspection problems including detecting car and truck bombs, combating weapons smuggling, and imaging cargo to expose trade fraud and illegal immigration. AS&E's patented Z® Backscatter technology detects plastic explosives, illegal drugs, and other contraband, even when artfully concealed in complex backgrounds by terrorists and smugglers. AS&E's Shaped Energy™ X-ray inspection systems combine material discrimination features of Z® Backscatter imaging with the penetration capability of high-energy X-rays for dense cargoes. AS&E's High Energy Systems Division manufactures linear accelerators for a variety of applications including medical, scientific, security, electron beam curing and non-destructive testing. For more information on AS&E products and technologies, please visit AS&E's web site at http://www.as-e.com.

For more information:
Ted Owens
American Science and Engineering, Inc.
(978) 262-8700

Safe Harbor Statement

The foregoing press release contains statements concerning AS&E's financial performance, markets and business operations that may be considered ``forward-looking" under applicable securities laws. AS&E wishes to caution readers of this press release that actual results might differ materially from those projected in any forward-looking statements. Factors which might cause actual results to differ materially from those projected in the forward-looking statements contained herein include the following: significant reductions or delays in procurements of the Company's systems by the United States and other governments; disruption in the supply of any sole-source component incorporated into the AS&E's products; litigation seeking to restrict the use of intellectual property used by the Company; potential product liability claims against the Company; global political trends and events which affect public perception of the threat presented by drugs, explosives and other contraband; global economic developments and the ability of governments and private organizations to fund purchases of the Company's products to address such threats; and the potential insufficiency of Company resources, including human resources, capital, plant and equipment and management systems, to accommodate any future growth. These and certain other factors which might cause actual results to differ materially from those projected are more fully set forth under the caption ``Forward-Looking Information and Factors Affecting Future Performance" in the Company's Annual Report on Form 10-K for fiscal year ending March 31, 2002.

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American Science and Engineering, Inc. Names Dr. Roger Heinisch Interim CEO