THE U.S. NATIONAL SECURITY AGENCY (NSA) UTILIZES ELECTRONIC EQUIPMENT TO CONDUCT WARRANTLESS SEARCHES OF INTERNATIONAL ELECTRONIC COMMUNICATIONS BY AMERICANS. NSA COMPUTERS SCRUTINIZE INTERNATIONAL MESSAGES AND, THROUGH A PROCESS CALLED WATCH LIST SURVEILLANCE, SELECT THOSE WITH CERTAIN CHARACTERISTICS, SUCH AS MESSAGE DESTINATION OR SELECTED KEY WORKS, FOR FURTHER STUDY WITHIN NSA AND POSSIBLE DISSEMINATION TO OTHER FEDERAL AGENCIES. THE NSA AND ITS SURVEILLANCE TECHNIQUES ARE DESCRIBED, FOLLOWED BY AN EXAMINATION OF THE LEGITIMACY OF WARRANTLESS WATCH LIST SURVEILLANCE IN LIGHT OF THE FOURTH AMENDMENT'S PROHIBITION OF UNREASONABLE SEARCHES. QUESTIONS OF WHETHER WATCH LIST SURVEILLANCE CONSTITUTES A SEARCH ARE CONSIDERED, ALONG WITH THE APPLICABILITY OF EXISTING WARRANT REQUIREMENT EXCEPTIONS, INCLUDING THE FOREIGN INTELLIGENCE SURVEILLANCE, BORDER SEARCH, STOP AND FRISK, ADMINISTRATIVE SEARCH, AND CONSENSUAL SEARCH EXCEPTIONS. THE PRIORITY OF A NEW WARRANT REQUIREMENT EXCEPTION FOR WATCH LIST SURVEILLANCE IS CONSIDERED, WITH ATTENTION TO PROTECTIONS PROVIDED BY SUCH A WARRANT REQUIREMENT AND ITS IMPACT ON FOREIGN INTELLIGENCE GATHERING. IT IS ARGUED THAT PRIOR JUDICIAL REVIEW OF NSA WATCH LIST SURVEILLANCE IS CONSTITUTIONALLY REQUIRED AND AN APPROPRIATE STANDARD FOR SUCH JUDICIAL REVIEW IS PROPOSED. IN DECIDING WHETHER TO ISSUE WARRANTS FOR WATCH LIST SURVEILLANCE, COURTS SHOULD CONSIDER THE SAME FACTORS APPLICABLE TO AREA SEARCHES, MODIFIED AS FOLLOWS TO SUIT NSA SURVEILLANCE: (1) THE IMPORTANCE OF THE DESIRED INTELLIGENCE INFORMATION TO THE GOVERNMENT; (2) THE LIKELIHOOD THAT THE INFORMATION WILL BE IN THE COMMUNICATION STREAM TO BE INTERCEPTED AND THE PROBABILITY THAT IT WILL BE EXTRACTED USING THE WATCH LIST CRITERIA; (3) THE PROBABLE INTRUSION ON PERSONAL PRIVACY ENTAILED BY THE SURVEILLANCE; AND (4) WHETHER A LESS EXTENSIVE FORM OF SEARCH WOULD BE SUFFICIENT TO ACQUIRE THE INFORMATION. RELEVANT JUDICIAL DECISIONS ARE FOOTNOTED. (KBL)