With Voice over IP technology (VoIP), an innovation has emerged that has the potential to completely replace the circuit-switched telephone network. The technology is mature, cost-effective, and nearly universally available. The diffusion of this innovation is an interesting phenomenon of technological change from both practical and scientific perspectives. Michael Hensel and Jan Wirsam analyze and evaluate different diffusion models and assess their applicability to VoIP. Based on the model analysis, insights regarding technology selection are derived, and strategic and tactical considerations are provided in the form of marketing-related thoughts. The book is aimed at lecturers and students of business administration with a focus on marketing and innovation management, as well as managers involved in the dissemination of innovations.