Efforts to use eye movement data to elucidate cognitive processes center on phenomena ranging from basic physiological processes to complex processes such as decision-making and job performance, and have been very productive. Irrespective of the particular task being studied, individual differences efforts have yielded differences in eye movements at five levels: (1) stages or phases; (2) differences in the sequential distribution of processing activities; (3) strategy components and strategies; (4) differences in eye movement patterns over time attributable to learning; and (5) flexibility, which occurs when an individual maintains processing efficiency as the demands of a task change. A categorized bibliography of eye movement research in the above areas is provided. (Contains 140 references.) (Author/JDM)