MARK ARONOFF The articles included in this section represent recent research on morpholog­ ical classes which has been independently performed by a number of investi­ gators. This work was presented at a symposium that was organized as part of the 1990-1991 annual meeting of the Linguistic Society of America in Chicago in January 1991. Our aim in presenting this work is twofold: on the one hand, we would like to encourage others interested in morphology to pursue the types of research that we present. This is especially important in the study of morphological classes, which, while they are widespread among the languages of the world, are