This study investigates the effects of two organizational variables (market orientation and organizational innovativeness) and the interaction between these two variables on supply chain agility as well as examines the moderating effect of 1) firm size and 2) the extent of global sourcing. Employing a web-based e-mail survey method, the study issued 1,320 questionnaires to South Korea apparel manufacturing companies; data from 147 completed surveys were analyzed. Market orientation, organizational innovativeness, and the interaction between the two variables positively affect supply chain agility. Firm size and global sourcing do not have any significant moderating effects on the relationship between organizational characteristics and supply chain agility. Companies with high market orientation and high organizational innovativeness have more agile supply chains than companies with only market orientation or organizational innovativeness. Firms need to effectively enhance market orientation and organizational innovativeness simultaneously to enhance supply chain agility. The lack of a moderating effect from firm size suggests that all companies should promote a greater degree of market orientation and organizational innovativeness to enhance supply chain agility regardless of firm size.