This paper is mainly devoted to reviewing past research on music development. Some recommendations for future research on music development and for improving music education for preschool children are also included. The developmental theories of Jean Piaget are discussed in detail, with special attention being given to concepts important to research on music development (i.e., symbolic thinking, conservation, and reversibility of thought). The concepts of musical intelligence and musical memory are discussed along with four stages of artistic development, which correspond to the Piagetian stages of cognitive development, proposed by Dennie Wolf and Howard Gardner (1980). Research is summarized on aural awareness and on discrimination and memory of infants, toddlers, and young children. Studies which are reviewed because they are representative of the field include work by Heinz Werner (1917), the Pillsbury Foundation studies (1937-1948), research based on the concept of conservation, and Jeanne Bamberger's study of children's pictorial representation of rhythm sequences (1982). Finally, it is recommended that future research include both observational and experimental data, that there be more longitudinal studies, and that researchers use tasks that are not verbally oriented. It is also recommended that efforts be increased to make knowledge about young children's music development available to professional child caregivers. (CB)