Knowledge is the core factor that helps to maintain innovation. It can be shared or travel from one firm to another. When two companies have experience working together, they build a relationship-specific intellectual capital. It cannot be appropriated when pairings with other firms. If the relationship is damaged, the capital is lost and the productivity decreases. This knowledge motivates firms to maintain long-term relationships. Three aspects of inter-firm learning are the acquisition of substantial knowledge (about products, technology, or markets) from distributors, the learning about collaborating with each distributor, and the general firm’s knowledge about managing distributors.