Extant literature focuses on within-dyad opportunism (i.e., transgression of the norms of a specific business relationship) while neglecting pro-relational opportunism (i.e., transgression of societal norms to benefit the relationship), resulting in limited understanding of their different effects. We argue that opportunism is a significant threat to the identity of business partners and boundary spanners which results in different relational dynamics at different levels, that is, Type-I (i.e., interorganizational identification squeezing out interpersonal identification) and Type-II identification asymmetry (i.e., interpersonal identification dominating interorganizational identification). Identification asymmetry further mediates the effects of opportunism on exchange performance. Based on a matched manufacturer–supplier sample, we find strong support to the hypotheses. Moreover, distributive fairness aggravates the effect of pro-relational opportunism on identification asymmetry, while interactive fairness mitigates it. Our research provides more nuanced between-level findings on identification in interorganizational settings, and cautions against firms’ tendency toward Machiavellian reasoning when they face the temptation of complicit behavior for organizational gains.