An intensive study of twenty five primary classrooms with and without aides suggested that teachers with aides displayed more evidence of job satisfaction in teaching and were able to devote more time to teaching activities they valued. Teachers with aides were able to devote more time to instruction and less time on classroom management. There was no marked evidence that teacher aides altered the teacher's ability to individualize instruction or to create greater pupil involvement. Teachers interviewed preferred spending money on a teacher aide than on classroom materials, equipment, or consultants. (Author)