[en] The European Power Plant Conceptual Study (PPCS) has been a study of conceptual designs for commercial fusion power plants. It focused on five power plant models, named PPCS A, B, AB, C and D, which are illustrative of a wider spectrum of possibilities. The PPCS study highlighted the need for specific design and R and D activities as well as the need to clarify the concept of DEMO, the device that will bridge the gap between ITER and the first fusion power plant. An assessment of the PPCS models with limited extrapolations has led to the clarification of the objectives of DEMO. Many parameters will have to be controlled in DEMO in order (1) to control the machine, (2) to satisfy the testing requirements, (3) to satisfy regulatory requirements (primarily safety), and (4) to protect the investment. On the other, DEMO will ulilise one or two plasma scenarios only