Th study of two-piano music was prompted by an active interest in that field and a recognized need for a knowledge of its literature on the part of the writer, who, for the past five years, has devoted most of her time to two-piano work. After careful investigation it becomes apparent that no other study similar to this has yet been made, and it is hoped that it may be helpful to others with interests in common. Much remains to be done and further study would prove profitable. More information might be gained from interviews with prominent duo-pianists, as well as from examination of foreign catalogues and of recital programs given in Carnegie Hall, Town Hall, and similar music centers.