4. Hypotheses
The central proposition that is explored here is that imports do fill a crucial role in the internationalization of US firms. In a
stage theory of internationalization, we assert that imports may well be the first step in the firm's learning and subsequent
decisionmaking about cross-border business activity. In a broader context of international business networks, we look at how imports may be related to exports and overall firm strategy through the supply chain. As a mechanism for organizational learning, we see imports as a key stage for obtaining information and knowledge about foreign supply and market conditions, as well as for obtaining technology and skills from foreign suppliers. And subsequently we look at several specific types of firm to identify how imports are expected to operate differently across categories of firm. This perspective is presented through the hypotheses below, followed by an explanation of the underlying logic for each one. The first two hypotheses relate to imports in all of the firms in our sample, and the following three hypotheses relate to divisions between categories of firms.