This thesis examines the importance of sourcing and procurement best practices through an overview of the make-or-buy decision and a case study of the Deepwater Horizon disaster that took place in the Gulf of Mexico in 2010. A review of literature and various industry examples have been used to demonstrate the importance of building sustainability into sourcing and procurement decisions at the beginning of supply chain activities. By increasing upstream visibility and holding partners to consistent standards of sustainability, firms can successfully mitigate risk and improve return on investment. Several different sourcing and procurement examples are highlighted and compared to the main case study that investigates the social, economic, and environmental implications of BP’s supply chain management decisions over the past three decades.