Over time, according to popular and academic accounts, alternative trade initiatives [such as fair trade, organics, forest certification, and socially responsible investing ] almost invariably lose their oppositional stance and go mainstream. That is, they lose their alternative, usually peripheral, and often contrarian character. In this paper, I argue that this is not always the case and that the path to going mainstream is not always an unproblematic one. I observe that while scholars have documented various aspects of specific alternative (...) trade initiatives, little comparative work has been done to theorize their different trajectories. To advance the scholarship, I compare two alternative trade movements, fair trade and SRI, and develop three hypotheses—the relation motivations hypothesis, the material interests hypothesis, and the organization of credibility hypothesis—that explain why going mainstream has been so hotly contested in the fair trade movement but not the SRI movement. I articulate these hypotheses and evaluate their merits. (shrink)