IN DEMONSTRATING THE FACILITATIVE EFFECT OF AVAILABLE PAST INSTANCES IN CONCEPT LEARNING, IT WAS PREDICTED THAT AVAILABILITY WOULD BE FACILITATED WHEN SUBJECTS WERE PROVIDED WITH A CORRECT RECORD (CR) OF CLASSIFICATION. IT WAS ALSO PREDICTED THAT SUBJECTS MORE CAPABLE OF RECALLING THE CORRECT CLASSIFICATION OF PAST INSTANCES WOULD PROFIT LESS FROM THE AVAILABILITY OF A CR, WHILE SUBJECTS LOW IN ASSOCIATIVE MEMORY WOULD PROFIT MORE FROM AN INCREASE IN THE NUMBER OF INSTANCES INVOLVED IN THE CR. SOME 59 HIGH-SCHOOL STUDENTS WERE ADMINISTERED A SHORT-TERM MEMORY FOR ASSOCIATIONS TEST AND A CONCEPT LEARNING TASK INVOLVING A FOUR CATEGORY, TWO-DIMENSIONAL CONJUNCTIVE CONCEPT PROBLEM. THE RESULTS INDICATE THAT THE AVAILABILITY OF A CR WAS HIGHLY FACILITATIVE. HOWEVER, THE HYPOTHESIS THAT SUBJECTS LOW IN MEMORY WOULD PROFIT MORE FROM INCREASING AVAILABILITY WAS NOT CONFIRMED. IT WAS CONCLUDED THAT FOR AVAILABILITY TO BE FACILITATIVE, THE SUBJECT MUST BE PROVIDED WITH INFORMATION RELEVANT TO THE SOLUTION OF THE TASK. GIVEN THAT SUCH INFORMATION IS AVAILABLE THERE IS AN OPTIMAL LEVEL OF AVAILABILITY OF SUCH INFORMATION WHICH IS, AT LEAST IN PART, A FUNCTION OF THE SUBJECT'S ABILITY TO UTILIZE IT EFFICIENTLY. THIS PAPER WAS PRESENTED AT THE ANNUAL MEETING OF THE AMERICAN EDUCATIONAL RESEARCH ASSOCIATION (CHICAGO, FEBRUARY 1968). (CG)