[en] Full text of publication follows. For industry, materials R and D needs are dependent on specific market prospects and on the possibility of going from laboratory results to industrial applications within a reasonable period of time. HTR can be considered in some cases for electricity generation, but the main incentive for this type of system is its possible use for industrial process heat applications without CO₂ emission. It is also the main challenge for its development, as there is no experience at all of a direct coupling of a nuclear heat source with an industrial process without intermediate conversion into electricity. The specifications of the system to be developed, in particular' but not only the operating temperature, will depend of the precise characteristics of these applications. As far as the operating temperature is concerned, there are many industrial applications with high heat consumption at temperatures significantly below 800 deg C and also other applications which require much higher temperatures. AREVA, together with its partners CEA and EdF, with the contribution of the European project RAPHAEL of the 6. Framework Programme and possibly in the future additional inputs from the VHTR materials project of the Generation IV International Forum, has undertaken a large R and D programme for assessing the potential of materials which can be available on an industrial basis for being used for critical HTR components, in particular the Intermediate Heat Exchanger (IHX), unavoidable for heat applications, the reactor vessel, the internals and the control rods. From the results already obtained, it appears that the materials which could be available for an industrial development as soon as possible (next decade) have performance limits that would not authorize operating temperatures much above 800 deg C. In the longer term, if real market needs are identified, more advanced materials could be considered, but it is clear that they require a lot of R and D, not only to optimise them and assess their performance, but also to develop processes for forming and assembling them, which, very often do not exist at all for the time being. Now the challenge is not only to develop and qualify high performance materials, but also to develop and manufacture high performance components made from these materials. Some of these components, in particular the IHX, are beyond the industrial state of the art, even if the aim is not to reach very high temperatures. Their development will require an extensive R and D and qualification programmes, which will necessitate large test facilities producing actual operating conditions (impure helium atmosphere, high temperature, transients). Therefore the priorities of the development programme should be put in the right order: first of all, to make the demonstration of industrial feasibility of the coupling of a large scale reactor with an industrial process heat application at a reasonable temperature level, and therefore to develop and qualify the materials and components needed for the reactor and the coupling, then, in the longer term, to search for solutions for higher performances in terms of temperature, fuel burn-up, availability, lifetime, etc., if required by the market. (authors)