The current global events have exposed areas for improvement in sourcing, contracting, and managing suppliers, in addition to demonstrating the importance of good supply chain management. Making the right choice from a supplier pool requires balancing a variety of criteria. To improve their success and competitiveness, businesses need a clear understanding of the supplier selection process. This research investigates how various supplier selection criteria might affect a firm’s procurement efficiency in a developing country environment.Based on a multiple case study strategy, this paper puts forward the supplier selection criteria that are considered most important for oil and gas companies in Nigeria. The analyses highlight key measures of procurement efficiency in the industry. Researchers and practitioners can use this information to prioritise the most relevant selection criteria while acknowledging the relevant efficiency indicators within the oil and gas context.