Many B-to-B exchanges have failed in recent years, but a few operators survived the hype and reached the break-even point. What can be the rationale for the persistence of such operators in the market? The evidence suggests that these operators have enlarged their activity in recent years, integrating more services in their offerings, and now they are able to have an impact on the competitiveness of participant firms, which goes beyond the mere effect on transaction costs. Focusing attention on firms, and using a resource-based approach, it is possible to determine the potential competitive effect of a firm participating in a B-to-B exchange. Beyond the well-known effect on negotiation capabilities, firms may also extract value from internal activity management and from inter-organizational network participation, improving efficiency and exploiting partnership opportunities; specific resources support these drivers of value creation, with different competitive features.