  Remarkable progress has been made in diagnosing energetic particle
instabilities on present-day machines and in establishing a theoretical
framework for describing them. This overview describes the much improved
diagnostics of Alfven instabilities and modelling tools developed world-wide,
and discusses progress in interpreting the observed phenomena. A multi-machine
comparison is presented giving information on the performance of both
diagnostics and modelling tools for different plasma conditions outlining
expectations for ITER based on our present knowledge.
