The evolution of communications based on Internet technology allows considering the development of Virtual Workspaces. Recently, modeling formalisms have been proposed to specify the interactions among the various members of a workgroup interacting through a virtual space. Moreover, depending of the nature of the tasks developed by the workgroup, not all the communication resources based on internet are necessary. In this context, this paper introduces a design process of customizable virtual work spaces. The proposed process specifies the components of the virtual workspace architecture necessary to support the workgroup task. The process leads the specification based on the modeled interactions among members.