Vaccines have historically been considered to be the most cost-effective method for preventing communicable diseases. It was a vaccine that en? abled global eradication of the dreaded disease smallpo. .The papers in this volume were presented at Symposium on Progress in Vaccinology, 1-5 December 1986, New Delhi, IndiaVaccines have historically been considered to be the most cost-effective method for preventing communicable diseases. It was a vaccine that en? abled global eradication of the dreaded disease smallpo. .I Opening Remarks.- 1. Vaccinology: The Two Revolutions.- II Public Health PerspectiveThe Present Scene.- 2. Vaccinology and the Goal of Health for All.- 3. Toward Universal Immunization: 1990.- 4. New and Improved Techniques for Vaccine Production.- 5. Transfer of Vaccine Production to the Developing World: Rabies Vaccine.- 6. Policy for Developing Countries for Storage, Distribution, and Use of Essential Vaccines for Immunoprophylaxis.- III Environmental Factors Modulating The Efficacy of The Vaccine.- 7. Immunity in Tuberculosis: Environmental Versus Intrinsic Factors Modulating the Immune Responsiveness to Mycobacteria.- 8. Geographic Variation in Vaccine Efficacy: The Polio Experience.- IV Hepatitis.- 9. Molecular Immunology of Viral Antigens in Hepatitis B Vaccinations.- 10. Biologic Significance of Pre-S Antigen and Anti-Pre-S Antibodies in Hepatitis B Virus Infection.- 11. Enterically Transmitted Hepatitis Viruses: Prospects for Control.- 12. Immunological Characterization of a Viral Agent Involved in Epidemic and Sporadic Non-A Non-B Hepatitis.- V Gastrointestinal Infections.- 13. Attenuated Oral Typhoid Vaccine Ty 21a.- 14. Oral B SubunitWhole Cell Vaccine Against Cholera: From Basic Research to Successful Field Trial.- 15. Prospects of Immunization Against Cholera by Adhesive Antigen.- 16. Protective Antigens of Vibrio cholerae.- 17. Rationale for the Development of a Rotavirus Vaccine for Infants and Young Children.- 18. Mucosal Immunity in lC(