The continuing and increasing trade uncertainties have exposed firms to a global market with an unprecedented level of competition, leading to global sourcing of intermediate inputs in order to improve firm competitiveness. Nowadays, owning an efficient global supplier base constitutes an important source of firm's advantage to survive and thrive. For firms located in developing countries such as China, sourcing from foreign origins promotes firm productivity, product scope, and also affects the other aspects of firm performance. The goal of this project is to improve our understanding of the constraints that heterogeneous firms face in expanding and maintaining their global supplier network and in responding to unanticipated trade shocks to this base. As Chinese firms became more inclined to import foreign inputs, many discovered that their newly created relationships with suppliers could be harmed by unanticipated trade shocks. This risk becomes increasingly severe during the recent trade war period. We use this unique setting in China to learn how firms manage their supplier base and to obtain insight into the limits of their ability to adjust to adverse trade shocks quickly, with a particular interest in the firms that are located in the Greater Bay Area (GBA) since they are mostly export oriented and heavily participating in the global value chain.