This thesis comprises three independent essays on supply chain management. In the first essay we collect data on 27,000 vertical relationships to study the importance of different channels of productivity spillovers between upstream and downstream firms. We explore the relative influence of two types of channels: endogenous and exogenous. The endogenous channel measures how a firm's productivity is affected by knowledge transfers (arising from collaboration and peer-mentoring). The exogenous channels measure the extent to which productivity is influenced by the partners' characteristics (e.g. geographic location, inventory turnover, financial leverage, etc.). We find that the endogenous channel is the primary source of spillovers. We also f...