The goal of the MYRRHA project is to demonstrate the technical feasibility of transmutation in a 100 MWth accelerator-driven system (ADS) by building a new flexible irradiation complex in Mol (Belgium). The MYRRHA facility requires a 600 MeV accelerator, delivering a maximum proton flux of 4 mA in continuous operation, with an additional requirement for exceptional reliability. This paper will briefly describe the present status of this ADS accelerator design, and will then focus on fault tolerance aspects and their impact on the beam operation, and the ongoing R&D activities. This work is being supported by the European Atomic Energy Community’s (EURATOM) Seventh Framework Program under grant agreement n°269565 (MAX project).