Various important benefits can be achieved through the successful management of offshore outsourcing. Numerous studies exist on outsourcing in general, yet the large extant literature on offshore outsourcing has dealt with information technology (IT) outsourcing from the client's perspective. Several frameworks, focusing on guiding information systems managers, for IT outsourcing have been developed. However, none of these frameworks attempted to provide a holistic guideline to manage the entire process of offshore outsourcing of software production. There is a significant lack of studies dealing with the management of offshore outsourcing of software production from both the vendor's and client's perspectives. Thus, there is a great need for studying such a multifaceted and complex phenomenon more deeply from both scenarios to find out the best practices for managing the unified process. In this study, we utilize the conceptual framework of The ICT-supported Unified Process Model of Offshore Software Production Outsourcing as our research model. We then validate this model by reviewing the large extant literature, and conducting multiple case studies from both the vendor's and client's viewpoints, where professionals with extensive experience in managing offshore outsourcing of software production are interviewed. The implications of the findings are discussed for both practical and research purposes.