Part I. Systems of Communication: Introduction and Review U. Jurgens; 1. Evolution of Vocal Communication D. Ploog; 2. On the Neurobiology of Vocal Communication U. Jurgens; 3. Vocal Affect Expression as Symbol, Symptom and Appeal K. R. Scherer; Part II. Noncategorical and Categorical Symbols in Primate Communication: Introduction and Review K. Bard; 4. Animal Signals: Motivational, Referential, or Both? P. Marler, Ch. Evans and M. Hauser; 5. Noncategorical Vocal Communication in Subhuman Primates: The Example of Common Marmoset Phee Cells J. D. Newman and P. Goedeking; 6. Categorical Vocal Signaling in Subhuman Primates M. J. Owren, R. M. Seyfarth and S. L. Hopp; 7. Vocal Development in Nonhuman Primates D. Symmens and M. Biben; Part III. Development of Nonverbal Vocal Signals in Humans: Part I. From Cry to Speech Sounds: Introduction and Review R. Eilers; 8. No Language But a Cry B. M. Lester and C. Z. Boukydis; 9. Development of Vocal Signaling in Human Infants: Toward a Methodology for Cross-Species Comparisons D. K. Oller and R. E. Eilers; 10. Disorders of Vocal Signaling in Children H. Amorosa; Part IV. Development of Nonverbal Vocal Signals in Humans: Part II. Interactive Support in Preverbal Dialogues: Introduction and Review R. Eilers; 11. Early Ontogeny of Reciprocal Vocal Communication in Precanonical Parent-Infant Interactions M. Papousek; 12. Didactic Interactions: Intuitive Parental Support of Vocal and Verbal Development in Human Infants H. Papousek and M. Bornstein; 13. Meaningful Melodies in Mothers' Speech to Infants A. Fernald.