It identifies three values that underlie the Sixth Amendment right-to-counsel clause (fairness, attorney-client privacy, and autonomy interests of the accused) by examining several U.S. Supreme Court cases, with attention to the possible role played by attorney-client privacy protection as a basis for the Court's decisions. The relevant cases are in two categories: situations in which the government infiltrates an actual attorney-client conference, and, as in "Massiah" and its progeny, the government engages an accused outside the presence of counsel at a time when the right to counsel has been triggered by the initiation of adversarial proceedings. The discussion then reviews lower court opinions and documents the substantial disagreement among those courts regarding the role of attorney-client privacy protection as a Sixth Amendment value. Building on an opinion of Chief Judge Richard A. Posner of the Seventh Circuit Court of Appeals, this article then derives principles recommended as useful vehicles for defining the proper scope of Sixth Amendment privacy. These principles are then applied to the relevant body of U.S. Supreme Court case law to illustrate that privacy protection is not a relevant value in those cases. Finally, the article urges judicial clarification of the function of attorney-client privacy in right-to-counsel cases and recommends principles to aid in this clarification. 284 notes