This study traces the way in which the librarian as the guardian of the freedom to read came to replace the librarian as moral censor. This shift in ideology is traced against a backdrop of major social and literary changes. Within this context, censorship is treated as part of a broader professional ideology of book selection. Geller treats that ideology in terms of three constant dilemmas of choice: populism vs. elitism, neutrality vs. advocacy, and freedom vs. censorship. By exploring the ways in which librarians as public servants have defined their selection policies in terms of the public interest, she sheds new light on the complex historical background and shifting social values that underlie contemporary policy alternatives.