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Humans process a visual display more efficiently when they encounter it for a second time, showing learning of the display. This study tests whether implicit learning of complex visual contexts depends on attention. Subjects search for a white target among black and white distractors. When the locations of the target and the attended set (white distractors) repeat, search speed is enhanced; but when the locations of the target and the ignored set (black distractors) repeat, search speed is unaffected. This suggests that the expression of learning depends on attention. However, during the transfer test, when the previously ignored set becomes attended, it immediately facilitates performance. In contrast, when the previously attended set becomes ignored, it no longer enhances search speed. We conclude that the expression of visual implicit learning depends on attention, but latent learning of repeated information does not. (140 words) The role of attention in perception and memory is one of the longest standing debates in cognitive psychology. Extensive evidence suggests that perception and memory are attentiondependent