This paper provides a new explanation for the dominance of multinational corporations (MNCs) in international trade: after being acquired by an MNC, firms face lower entry frictions in countries in which their global parent already has a presence. We provide a model of firms’ export and import choices that delivers firm-level gravity regressions to isolate these “MNC network effects” from other channels through which multinational ownership can affect firms’ trade participation. We estimate the model combining rich administrative data for Belgium with data on MNCs’ global affiliate networks. Event study results reveal that acquired firms are more likely to start exporting to and importing from countries that belong—or that are exogenously added—to their parental network. The effects are stronger when new affiliates are geographically and culturally close to their direct parent, which can facilitate transfer of information about the global parent’s network. Combining the structure of our model with the empirical estimates, we find that MNC network effects have a large impact on firm growth. The effects of MNC ownership extend beyond the boundaries of the multinational: new affiliates are also more likely to start trading with countries that are geographically and culturally close to the MNC network, even if their parent has no affiliates there.