Abstract Probably no concept has been studied as long in the experimental study of memory as that of serial learning-that is, learning a series of items in order. Clearly, recalling things in the proper order is crucial in limited situations, such as remembering telephone numbers or word spellings. More generally, however, any skilled behavior critically depends on the mastery of order. Consider the most distinctively human skill-that of language. At least among adults, information is generally carried not by the use of novel stimuli but by the ordering of long-familiar words and phrases.