Building on equity theory, we integrate trust-repair and response-to-opportunism studies to distinguish individual boundary spanner opportunism from firm opportunism and examine how these two types of opportunism influence the effect of collaboration on post-opportunism trust restoration, a crucial yet challenging context for trust development. We further examine the effect of two alternative strategies to collaboration: tolerance, and aggression on post-opportunism trust restoration. Using 574 confidential reports of senior managers working for 287 industrial buyers, we find that collaboration is the most effective strategy for post-opportunism trust restoration. More importantly, our findings show that although collaboration restores trust under both types of opportunism, it fits better with individual boundary spanner opportunism than with firm opportunism. In comparison, tolerance has a positive effect on trust restoration under boundary spanner opportunism but negatively affects trust under firm opportunism, while aggression hinders trust restoration even more under firm opportunism than it does under individual boundary spanner opportunism.