SUMMARY
This article presents some keywords and concepts concerning free improvised music and its recent developments drawing from ongoing bibliographical research. A radical pluralism stems from musicians' backgrounds and the mixtures and fusions of styles and idioms resulting from these mixtures. Seemingly very diferent "performance-driven" and "play-driven" attitudes exist, even among musicians who share the practice of performing at concerts. New models of musical analysis aiming specifcally at free improvised music take into account these interactional dimensions and point to the existence of certain typical sounding characteristics.