THE SAMPLE CONSISTED OF 40 PAIRS (CREWS) OF POLICE PATROL OFFICERS WHO CONSENTED TO ALLOW A CIVILIAN OBSERVER TO ACCOMPANY THEM DURING THEIR 8-HOUR SHIFT. OF THESE, HALF WERE COMPRISED OF ALL-MALE CREWS, AND HALF CONSISTED OF MIXED SEX CREWS CONTAINING ONE MALE AND ONE FEMALE. THE OBSERVER CODED THE TYPES OF PATROL ACTIVITIES ENGAGED IN AND VERBAL INTERACTIONS BETWEEN PATROL OFFICERS ON A PREESTABLISHED SCHEDULE. FOR EACH INDIVIDUAL IN EACH CREW, A DATA FILE WAS GENERATED FROM THREE SETS OF MEASURES: THE OBSERVATIONS OF PATROL ACTIVITIES AND VERBAL INSTRUCTIONS, AND THE RESPONSES FROM TWO SEX ROLE QUESTIONNAIRES. ANALYSIS OF VARIANCE CONTRASTING SEX AND CREW TYPE IN TERMS OF THE STRUCTURED OBSERVATIONS OF PATROL ACTIVITIES FOUND FEMALE OFFICERS LESS ASSERTIVE THAN MALE OFFICERS. MULTIPLE REGRESSION ANALYSES OF THE RELATIONSHIP OF SEX TO TOPIC INITIATED (POLICE WORK VERSUS INTERPERSONAL) RELATIONSHIPS VERSUS SOCIAL PAST-TIMES) REVEALED THAT FEMALE OFFICERS INITIATED INTERPERSONAL TOPICS MORE OFTEN THAN MALE OFFICERS. FURTHER ANALYSIS SHOWED THAT MIXED SEX CREWS INITIATED MORE NONJOB-RELATED CONVERSATION THAN DID SAME SEX CREWS. FINDINGS POINTED TO FACTORS WHICH HINDERED FEMALE OFFICERS FROM DEVELOPING MORE ASSERTIVE PATROL STYLES: (1) MALE OFFICERS' NEGATIVE EXPECTATIONS OF WOMEN ON PATROL, (2) DIFFERENT OPPORTUNITIES FOR THE SEXES TO PERFORM A VARIETY OF POLICE FUNCTIONS DUE TO MORE FREQUENT ASSIGNMENTS OF MIXED SEX CREWS TO LOW CRIME DISTRICTS, (3) DIFFERENCES FOR THE SEXES IN THE AMOUNT AND TYPE OF TRAINING RECEIVED WHILE ON PATROL, AND (4) DIFFERENCES IN THE TYPES OF MALES ASSIGNED TO MIXED SEX CREWS THAN TO SAME SEX CREWS. OVERALL, THIS STUDY WAS UNABLE TO DIFFERENTIATE BETWEEN INHERENT SEX DIFFERENCES AND THOSE ARISING FROM INEXPERIENCE AND INADEQUATE TRAINING. REFERENCES AND TABLES ARE INCLUDED. APPENDIXES PRESENT THE QUESTIONNAIRES AND OBSERVATION SCHEDULES. (WJR)