IN THIS STUDY ON THE EFFECTS OF STRUCTURE AND SEQUENCE ON ADULT LEARNING, 96 ADULTS UNFAMILIAR WITH NUMBER BASES AND RANGING IN AGE FROM 23 TO 53 WERE RANDOMLY ASSIGNED TO FOUR DIFFERENTIALLY STRUCTURED INTRODUCTORY MATERIALS (HISTORY OF MEASUREMENT, BASE TEN, BASE SEVEN, OR PRINCIPLES OF NUMBER BASES) AND TO THREE DIFFERENTIALLY SEQUENCED LEARNING TASK CONDITIONS (RANDOM, PARTIAL, OR COMPLETE) WITHIN FOUR INTELLIGENCE AND TWO SEX CATEGORIES. SUBJECTS WERE INDIVIDUALLY PRESENTED THE BASE FOUR TASK IN PAIRED ASSOCIATE FORM AFTER THEY HAD RECEIVED THE PROGRAMED INTRODUCTORY MATERIAL. THE INTRODUCTORY MATERIAL APPEARED TO HAVE SIGNIFICANTLY POSITIVE RESULTS ONLY WITH SUBJECTS HAVING SUPERIOR INTELLIGENCE. THE COMPLETELY SEQUENCED LEARNING TASK RESULTED IN A MORE RAPID MASTERY OF THE LEARNING TASK, ESPECIALLY WITH LESS INTELLIGENT SUBJECTS. RELIABLE DIFFERENCES AMONG THE INTELLIGENCE CATEGORIES AND BETWEEN THE SEXES WERE ALSO OBSERVED. (ALSO INCLUDED ARE CHARTS, TABLES, AND 17 REFERENCES.) THIS PAPER WAS PRESENTED AT THE NATIONAL SEMINAR ON ADULT EDUCATION RESEARCH, CHICAGO, FEBRUARY 11-13, 1968. (AUTHOR/LY)