With the help of Corporate Shared Services as a hybrid organizational form between in-house and external production, Bertelsmann aims to reduce IT costs by approximately 90 million euros, Philips intends to lower costs in indirect areas by about 170 million euros, Oracle plans to save around 1 billion US dollars through IT harmonization, Siemens seeks to cut its IT budget by approximately 800 million euros, and Deutsche Post World Net aims to reduce costs in external accounting by about 40%. Renowned companies such as Siemens IT Solutions and Services, SAP AG, BearingPoint, and Metaplan, along with prominent scholars, competently discuss strategies, concepts, and promising developments. The authors analyze the status quo, the competitive strategic effects, the challenges for controlling, organizational management, and the necessity of change management for the acceptance of Corporate Shared Services.