Advanced technologies such as the Internet and social media have transformed business models and spawned a myriad of innovative business practices that challenge traditional ways of doing things. One notable innovation is collaborative online shopping, dubbed “next wave in e-commerce” due to its unique appeals to social needs of shoppers. In contrast to solo online shopping, where shopping activities (e.g., product searching, product reviewing, and ultimate purchasing decision making) are performed by a single individual, collaborative shopping has multiple individuals engaged in the shopping activities together. At the core of collaborative online shopping lies the dynamic social interactions where shoppers engage task-oriented and socio-emotional communication activities. Despite the importance of these communication activities in collaborative online shopping, however, our review of the literature on collaborative online shopping discovers the lack of adequate attention to the two types of communication activities. What is more, the impact of shopping group structure in the collaborative online shopping context remains unknown. To address the research gap, we first develop the shopping group structure typology in the collaborative shopping context, and then drawing on Bales' Interaction Process Analysis and research on medial richness and consumer shopping behaviors, propose a conceptual framework of social interactions in collaborative online shopping. We postulate antecedents and outcomes of task and socio-emotional communication between co-shoppers in the collaborative online shopping context and delineate the moderating impact of shopping group structure. As an early effort examining shoppers’ communication activities and shopping group structure in the context of collaborative online shopping, our research offers insights that bear significant contributions to both academic researchers and industrial practitioners.