THE FORCIBLE ENTRY SAFEGUARD EFFECTIVENESS MODEL DEVELOPED AT SANDIA LABORATORIES IN NEW MEXICO PROCESSES BOTH DISCRETE AND CONTINUOUS EVENTS. DISCRETE EVENTS WOULD INCLUDE BEGINNING AND ENDING OF BARRIER BREAKS, ALARM TRIPS, ONSITE AND OFFSITE GUARD FORCE ALERTS AND ARRIVALS, BEGINNING AND ENDING OF A BATTLE, BARRIERS INSTALLED BASED UPON ALARMS, SABOTAGE COMPLETION, THEFT COMPLETIONS, AND DELAYING OF BATTLE TACTICS. CONTINUOUS EVENTS WOULD BE PRIMARILY THOSE INCIDENTS OCCURRING DURING A BATTLE BETWEEN INTRUDERS AND DEFENDANTS OF THE SITE. THE CHARACTERISTICS OF THE FIXEDSITE TO BE EVALUATED ARE REQUIRED FOR INPUT INTO THE MODEL. THE MODEL CAN SELECT THE ADVERSARY ATTRIBUTES AT RANDOM FOR VARIOUS ATTACKS AGAINST A GIVEN FIXED-SITE DESIGN. IN DEMONSTRATING THE USE OF THE MODEL WITH A HYOPOTHETICAL SITE, TRADEOFFS INVOLVING ONSITE AND OFFSITE RESPONSE FORCES AND RESPONSE TIMES, PERIMETER SYSTEM ALARMS, BARRIER CONFIGURATIONS, AND VARIYING LEVELS OF THREAT ARE ANALYZED. IT IS SHOWN HOW THE COMPUTER MODEL PROVIDES A FRAMEWORK FOR PERFORMING INEXPENSIVE EXPERIMENTS ON FIXED-SITE SECURITY SYSTEMS, FOR TESTING ALTERNATIVE DECISIONS, AND FOR DETERMINING THE RELATIVE COSTEFFECTIVENESS OF ALTERNATIVES. TABULAR AND GRAPHIC DATA ARE PROVIDED, ALONG WITH REFERENCES. (RCB) SA0901FA5337