UNDERCOVER OPERATIONS ARE ESSENTIAL TO THE INVESTIGATION OF ORGANIZED CRIME, NARCOTICS CRIME, RADICAL GROUPS, AND VICE OPERATIONS. THE MOST IMPORTANT CHARACTERISTICS THE UNDERCOVER AGENT MUST POSSESS ARE BELIEVABILITY AND THE ABILITY TO ACT CALMLY IN EMERGENCIES AND THREATENING SITUATIONS. THE FOLLOWING QUALIFICATIONS ARE NEEDED ALSO: BOTH UNIFORMED AND PLAINCLOTHES CRIME INVESTIGATION EXPERIENCE IN A HIGH INCIDENCE AREA; AGE, RACE OR ETHNIC BACKGROUND, AND CULTURAL TRAITS SUITABLE TO THE ASSIGNMENT; THE ABILITY TO MAKE SOUND DECISIONS; RESOURCEFULNESS; GOOD ACTING ABILITY; AND A GOOD MEMORY. A SINGLE PERSON OR A MARRIED PERSON WITHOUT CHILDREN IS ALSO PREFERRED. KNOWLEDGE OF ANOTHER LANGUAGE, OF STREET SLANG AND TERMS, OF MODUS OPERANDI, AND OTHER SPECIALIZED SKILLS ARE PLUS CHARACTERISTICS. THE IMPORTANCE OF KNOWING THE AREA TO BE INFILTRATED, THE PERSONS TO BE INVESTIGATED, SETTING UP A GOOD COVER STORY, ESTABLISHING GOOD COMMUNICATIONS, AND HAVING A WITHDRAWAL PLAN ARE DISCUSSED. AN IMPORTANT ASPECT OF UNDERCOVER WORK IS SOMETHING CALLED 'STYLE.' THIS HARD-TO-DEFINE FACTOR WHICH MAKES ONE AGENT MORE SUCCESSFUL THAN ANOTHER IS EXAMINED. MATCHING PERSONALITY TO ASSIGNMENT IS ALSO ESSENTIAL, AND EXAMPLES ARE PROVIDED. THE NEED FOR CAREFUL DOCUMENTATION AND THE PREPARATION OF EVIDENCE IS MENTIONED BUT NOT DISCUSSED AT LENGTH. (GLR)