SOME PRACTICAL PREVENTIVE MEASURES SUGGESTED BY THE DATA ARE: (1) CLERKS SHOULD GIVE PARTICULAR ATTENTION TO THE ACTIVITIES OF PRE-TEEN AND EARLY TEENAGE CUSTOMERS NOT IN THE COMPANY OF AN ADULT: (2) SECURITY SUPERVISORS SHOULD SCHEDULE SHOPLIFTING DETAILS TO WORK FROM NOON TO 9:00 P.M. FOR MAXIMUM PRODUCTIVITY; (3) IF A SUSPECT IS FEMALE, EXPECT THE STOLEN ITEM TO BE IN HER PURSE; (4) IF THE SUSPECT IS MALE, LOOK FOR THE ITEM TO BE IN HIS POCKETS OR CONCEALED UNDER HIS CLOTHING; (5) THE GREATEST SECURITY ATTENTION SHOULD BE GIVEN TO NONFOOD SUPERMARKET ITEMS, BECAUSE THEY ARE INVOLVED IN ABOUT 60 PERCENT OF THE THEFTS; AND (6) IN TERMS OF PARTICULAR ITEMS PREFERRED, WATCH FOR MALES TO TAKE LIQUOR AND CIGARETTES, WHILE FEMALES TEND TO SHOPLIFT CLOTHING AND SUNDRIES. ALL RETAILERS SHOULD CONVERSE WITH LAW ENFORCEMENT OFFICIALS ABOUT THE AMOUNT OF SHOPLIFTING LOSSES, SO THEFT PREVENTION WILL BE ASSIGNED THE PRIORITY IT DESERVES. IN 1978, 33 PERCENT OF THE ADULT SHOPLIFTERS APPREHENDED WERE REFERRED FOR PROSECUTION; AND IN JUVENILE CASES, 21.7 PERCENT WERE REFERRED TO THE POLICE. IN VIEW OF THE HIGH LOSSES TO SHOPLIFTING, THE MOST PRACTICAL APPROACH IS TO ESTABLISH A COST-EFFECTIVE PROGRAM WHICH BALANCES THE NUMBER OF PROSECUTIONS WITH THE GREATEST DETERRENT EFFECT. MERCHANTS SHOULD, THEREFORE, EXERCISE CONSIDERABLE RESTRAINT AND SELECTIVITY IN PROSECUTING SUSPECTS. PROSECUTION SHOULD BE SERIOUSLY CONSIDERED WHEN THE ITEMS INVOLVED ARE FRESH MEAT, LIQUOR, OR CIGARETTES, BECAUSE OF THE EASE WITH WHICH THESE ITEMS CAN BE SOLD ON THE STREET; AND WHEN A SHOPLIFTER IS A REPEATER, HAS NO IDENTIFICATION, AND HAS STOLEN NUMEROUS ITEMS OR ITEMS OF HIGH VALUE. 'GUILT' IN COURT IS MOST LIKELY TO BE ESTABLISHED WHEN (1) THE SUSPECT IS SEEN TAKING THE MERCHANDISE; (2) THE SUSPECT CONCEALS THE MERCHANDISE; (3) IT IS SEEN THAT THE MERCHANDISE IS NOT PURCHASED; AND (4) THE SUSPECT IS APPREHENDED AFTER HE OR SHE LEAVES THE STORE. TABULAR DATA ARE PROVIDED. (RCB)