Zappos.com is the world's largest online shoe and clothing retailer, generating $1 billion in annual sales. Its core competencies are delivering outstanding customer service and a delightful customer experience through its highly trained call center agents, next-day delivery, generous return policy, and strong corporate culture. However, in a more cost-conscious environment, Zappos will need to reduce expenses like surprise delivery upgrades while maintaining its focus on customer service to continue its sales growth.