In a preliminary study, passersby in a large shopping mall were significantly more likely to help a same-sex accomplice (by retrieving a dropped pen or providing change for a doUar) when these helping opportunities took place in the presence of pleasant ambient odors (e.g., baking cookies, roasting coffee) than in the absence of such odors. Participants also reported significantly higher levels of positive affect in the presence of pleasant odors. In a second study, the order in which passersby were exposed to a helping opportunity and rated their current mood was systematically varied. &sults similar to those of the first study were obtained; order of task had no effect on either mood or helping, but helping was significantly greater in the presence of pleasant fragrances than in their absence. In addition, there was some evidence that fragrance-induced increments in helping were mediated by increments in positive affect.