Older adults acquire new skills more slowly and less successfully than young adults. Why? One possibility that has received minimal empirical attention is that older adults' approach to the task (i.e., their strategy) may be different from young adults'. Preliminary research suggests that older adults do adopt different task strategies, such strategy differences do mediate age-related differences in skill acquisition, and the strategy use of older adults can be influenced by the structure of the task. The proposed research is designed to answer the following questions: (1) When do older adults use different strategies in skill acquisition tasks? (2) What are the mechanisms that underlie differential strategy use? (3) Is strategy selection of older adults amenable to change, or is it strictly limited by cognitive and speed abilities? (4) Can training and task structure be designed to enable older adults to use the optimal strategy? (5) How can strategy differences be incorporated into a general theory of age-related differences in skill acquisition? Twelve experiments are proposed to investigate strategy issues for young and older adults for a range of skills including perceptual learning, memory-based associative learning, and more complex skills such as learning to use an automatic teller machine and learning to make logic decisions. The proposed effort consists of three experimental series to systematically pursue the goals of identifying and understanding age-related differences in strategy selection, strategy use, and strategy adjustment. First, the costs and benefits of prior practice will be determined to assess the influence of nonspecific transfer on skill acquisition. Second, practice schedule manipulations will determine how task training should be structured to facilitate use of efficient strategies for learning. Third, the flexibility of strategy selection will be assessed with the goal of identifying the task components that lead to optimal strategy choice. The results of the proposed research will yield basic empirical data for a model of age-related differences in skill acquisition as well as practical information about how and when such age-related differences can be minimized through task design or appropriate training.