Adopting a multilevel perspective, this study proposed servant leadership as an antecedent to idiosyncratic deals (i-deals) at the individual and group levels (e.g., group median i-deals). Drawing from social cognitive theory, I hypothesized that i-deals positively relate to self-efficacy and that group median i-deals relate positively to group potency. Further, i-deals and self-efficacy were hypothesized to sequentially mediate the positive effect of servant leadership on individual performance, while the positive relationship between servant leadership and group performance was hypothesized to be mediated by group median i-deals and group potency sequentially. The hypothesized relationships were supported by data collected from 189 employees and their managers working in 45 groups of a Chinese manufacturing company.