THE FIRST SECTION ANALYZES THE CURRENT DISCOVERY RIGHTS AVAILABLE TO THE GOVERNMENT UNDER THE FEDERAL RULES OF CRIMINAL PROCEDURE AND DURING THE COURSE OF TRIAL. IN THE SECOND, THE CONCEPT OF PROSECUTORIAL DISCOVERY IS EXAMINED IN THE CONTEXT OF THE AMERICAN ACCUSATORIAL AND ADVERSARY CRIMINAL JUSTICE SYSTEM AND A SHIELD OF CONFIDENTIALITY WHICH SERVES TO CONFINE THE SCOPE OF PROSECUTORIAL DISCOVERY IS DELINEATED. THE AUTHOR CONCLUDES THAT THE EXPANSION OF PROSECUTORIAL PRETRIAL DISCOVERY RIGHTS HAS NOT BEEN PARALLELED BY A GROWTH IN THE UNDERSTANDING AND USE OF THE SHIELD OF CONFIDENTIALITY WHICH SURROUNDS AND PROTECTS THE DEFENDANT AND HIS LEGAL REPRESENTATIVES DURING CRIMINAL PROCEEDINGS.(AUTHOR ABSTRACT MODIFIED)...EB