American Science and Engineering, Inc. Announces Sale of Five More MobileSearch Systems to Mexico.

BILLERICA, Mass.--(BUSINESS WIRE)--Oct. 12, 1999--

American Science and Engineering, Inc. (AMEX:ASE) announced today that the Mexican Attorney General's Office (PGR) has agreed to purchase five additional MobileSearch(TM) systems to continue its campaign against drug and illegal immigrant smuggling. This order follows on the acceptance of the five systems delivered to Mexico earlier in the year.

Ralph Sheridan, Chief Executive Officer and President stated, "The Mexican government is making a major commitment to attack the problem of cocaine transiting through the country from Central America to the United States. The first five systems have demonstrated their value in finding drugs in vehicles and cargoes. In addition, we are supporting other law enforcement objectives in curbing the flow of illegal aliens into Mexico across the frontier with Guatemala and Belize.

"Over the last year, the PGR and AS&E have teamed together to enhance training programs for operational personnel and improved equipment design to deal with the harsh environment in remote Mexican locales. This experience has created a strong foundation for our continued support of the ambitious Mexican effort against illegal drugs in transit."

The MobileSearch system is part of AS&E's family of cargo and vehicle inspection systems. 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. AS&E has delivered more X-ray cargo inspection systems than anyone in the industry, and continues to be the leader in X-ray detection technology and applications.

AS&E develops and manufactures sophisticated X-ray inspection products for critical detection and security applications. AS&E's patented Z(R) Backscatter technology detects plastic explosives, illegal drugs, and other contraband, even when artfully concealed in complex backgrounds by terrorists and smugglers. For more information on AS&E products and technologies, please visit the Company's web site at http://www.as-e.com.

Safe Harbor Statement

The foregoing press release contains statements concerning the Company's financial performance and business operations which may be considered "forward-looking" under applicable securities laws.

The Company 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 statement 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 Company's products (of which there are several); 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; 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 "Risk Factors" in the Company's Registration Statement on Form S-3 (SEC File No. 333-9151).