In human studies, reported performance improvements with post-trial administration of nicotine have all involved associative learning (Mangan and Golding 1983; Colrain et al. 1992; Warburton et al. 1992). In this study, post-trial nicotine, obtained through smoking a cigarette, improved free recall of lists of unrelated words under conditions which limited the opportunity for associative learning. However, the nicotine-induced advantage was not observed when volunteers were required to complete a secondary (attention) task during the post-trial period in which they smoked. The results suggest that post-trial effects depend on the opportunity for stimulus processing after input, and that nicotine improves performance by increasing the attentional resources available for such strategic processing.