Plasma Material Interaction in Controlled Fusion Plasma Material Interaction in Controlled Fusion deals with the specific contact between the fourth state of matter i.e. plasma and the first state of matter i.e. a solid wall in controlled fusion experiments. A comprehensive analysis of the main processes of plasma surface interaction is given together with an assessment of the most critical questions within the context of general criteria and operation limits. It is shown that the choice of plasma facing materials can be reduced to a very limited list of possible candidates. Plasma Material Interaction in Controlled Fusion emphasizes that a reliable solution of the material problem can only be found by adjusting the materials to suitable plasma scenarios andvice versa.