Abstract: Social commerce is a new business model of e-commerce, which utilizes of Web 2.0 technologies and social media to support social-related exchange activities. While its popularity, being a subset of e-commerce, has been increasing tremendously since its introduction in 2005, there exists a general paucity of research on its framework and its applications’ effectiveness, especially in areas beyond the common social commerce practices. This study develops a comprehensive social commerce framework that has four key components: customer, merchant, platform and context. Then the study applies the cross-case synthesis technique to analyze the usability and generalizability of the framework by applying it to social commerce of two (one small and the other global) successful companies. We use the negative case analysis approach to assess the importance of the new component context by comparing a social commerce failure case with the two successful companies. Finally, we introduce a set of metrics for social commerce design. The proposed framework and its metrics are used to guide the design and evaluation of social commerce. This study makes a contribution to the social commerce literature in proposing a new design framework and to practice in providing insights for effective strategies of the online social business.