Located in the central Zhejiang province, Yiwu is a mountainous region originally inhabited by farmers. The poverty-stricken land left farmers with no option but commercial trading for a living. The city has a long history of being a hub for commercial trade. In the last two decades, the Yiwu international trade market has grown to be the world's largest small commodities market. This book studies the rapid development of 'Yiwu Business Circle' in the past two decades. Based on field research, the book analyzes the 'Yiwu Business Circle' from different levels such as the market system, supporting industry, merchant group and logistics network. The book also reveales the challenges and opportunities posed to 'Yiwu Business Circle' by the Belt and Road Initiative. It explores how the 'Yiwu Business Circle' will contribute to the Belt and Road Initiative by utilizing its strong business, logistics, capital and information flow platform that is established and shared by global manufacturers and merchants.