Customer service employees tend to react negatively to customer incivility by demonstrating incivility in return, thereby likely reducing customer service quality. Research, however, has yet to uncover precisely what customers do that results in employee incivility. Through transcript and computerized text analysis in a multilevel, multisource, mixed-method field study of customer service events (N = 434 events), we found that employee incivility can occur as a function of customer (a) aggressive words, (b) second-person pronoun use (e.g., you, your), (c) interruptions, and (d) positive emotion words. First, the positive association between customer aggressive words and employee incivility was more pronounced when the verbal aggression included second-person pronouns, which we label targeted aggression. Second, we observed a 2-way interaction between targeted aggression and customer interruptions such that employees demonstrated more incivility when targeted customer verbal aggression was accompanied by more (vs. fewer) interruptions. Third, this 2-way interaction predicting employee incivility was attenuated when customers used positive emotion words. Our results support a resource-based explanation, suggesting that customer verbal aggression consumes employee resources potentially leading to self-regulation failure, whereas positive emotion words from customers can help replenish employee resources that support self-regulation. The present study highlights the advantages of examining what occurs within customer-employee interactions to gain insight into employee reactions to customer incivility.