Research Question When marketing prosocial products, notably "green" products, how best to frame the promotional message? Past work suggests that, for promotions involving prosocial products, marketers must suitably balance egoistic versus altruistic reasons. This however begs the question whether marketers must use appeals that appeal to enhancing consumers' own self-image and ego, or appeals that appeal to consumers' desire to enhance the wellbeing of others, or both. Further, individual differences relating to environmental consciousness moderate the above result, impacting whether marketers should use egoistic appeals or altruistic appeals. The above work contributes to the work on "green marketing," an emerging but important product category, identifying how marketers can best promote such products. The above work more generally contributes to work on whether more number of reasons is always more persuasive, and simultaneously extends and counters extant findings on work relating to balancing egoistic versus altruistic appeals Method and Data We report results of two behavioral laboratory studies using over 336 undergraduate participants. In study 1, we used an ANOVA to examine the differences in purchase intentions and product attitude for different appeal types. We also used the PROCESS model 6 to find support for the proposed serial mediation model of: appeal type--single (altruistic or egoistic) or mixed (combination of altruistic and egoistic) messages → persuasion awareness → psychological reactance → purchase intentions and product attitude. In study 2, we use PROCESS model 2 to examine if the differences in environmental consciousness (measured using Green Values Scale) moderated the impact of appeal-type (egoistic appeals vs. altruistic appeals) on purchase intentions. Summary of Findings Results from Study1 show that mixing altruistic and egoistic reasons yield lower purchase intentions and unfavorable product attitude compared to when egoistic or altruistic messages are presented alone. Further results of serial mediation show that mixing egoistic and altruistic reason increases participant's awareness of the persuasive intent of the appeal, which in turn stimulates psychological reactance and thus diminishes intentions and attitudes. Results from Study 2 suggest that high EC consumers have higher purchase intentions when the persuasive message consists of prosocial reasons. On the other hand low EC consumers have higher purchase intentions when the message is framed using selfish reasons. Key Contributions This paper contributes to the literatures on green marketing. Given the importance of the green marketing domain, researchers have examined how best to structure advertising appeals. First, when marketing green products, this paper suggests that marketers are generally better off not using mixed appeals, i.e. a mix of egoistic appeals and altruistic appeals, as there is no condition wherein this is optimal. Second, marketers must choose between using only a set of egoistic appeals or only a set of altruistic appeals. When targeting more environmentally conscious consumers, marketers are relatively better off using a set of altruistic appeals; when targeting less environmentally conscious consumers, marketers are relatively better off using a set of egoistic appeals. Third, past work has shown that environmentally conscious consumers are more likely to buy green products; this work shows that this is more likely to be the case if marketers use altruistic appeals. However, if marketers use egoistic appeals in their advertising, then purchase of green products may be relatively less impacted by levels of environmental consciousness. [ABSTRACT FROM AUTHOR]