As competition in the e-commerce market enters a new phase in which big B2C platforms struggle with traffic growth and surging traffic acquisition prices, social media traffic has become a much-watched “blue ocean” of opportunity. Alibaba and JD.com, the giants of the sector, are as yet underequiped. Pinduoduo, born in the WeChat ecosystem, shows initial signs of success in social e-commerce, but faces sustainable development challenges following a period of explosive growth. This case will explore Pinduoduo’s driving forces and its potential direction.