This research is designed to elucidate the fundamental mechanisms of human information processing and retrieval. The empirical research is supplemented by quantitative models, generally stated in the form of computer simulations. The research is directed toward a wide variety of areas in the general domain of memory, retrieval, and forgetting. We shall explore: 1) The cue-dependent nature of retrieval, with particular emphasis upon the ways in which cues are combined when probing long-term memory; 2) The limitations upon capacity when retrieving, with emphasis upon the role of attention to cues; 3) The process of search in recall and the effects upon search of strategies; 4) The ways in which memory models can predict both accuracy data and reaction time data simultaneously; 5) Whether a single model can explain the results from recognition studies, category learning studies, and list-discrimination studies; 6) How recall and recognition of sentences can be related to recall and recognition of the words and elements making up those sentences; 7) Whether a retrieval model can explain the traditional findings in learning of items and lists; 8) Whether retrieval models can explain the traditional findings of "interference" encountered in learning of multiple lists. A special effort will be made in the proposed project to tie all of these areas together, both empirically and theoretically. We shall use as a starting point the SAM model that has already proved successful in predicting a great deal of data in the domains of recall and recognition, but shall also explore the relationships of the SAM model to other models. Our goal is the development of a comprehensive yet simple and consistent quantitative theory for the basic mechanisms of human information processing, learning, memory, retrieval and forgetting.