Museums often embody the public sphere, central sites where the display of sexual materials becomes a stage for debates over how and when the erotic is illicit. This essay explores how one mainstream museum struggled with these questions while mounting an exhibition on lesbian, gay, bisexual and transgender (LGBT) history in Chicago. Debates appeared over displaying sexually explicit materials in the gallery, and whether the exhibit would encourage visitors, particularly youth, to become sexually nonnormative or promiscuous. The museum embarked on a process of sharing authority with visitors to help navigate questions around displaying the illicit, which posed both opportunities and challenges. While the visitor panels supported the museum's process of making LGBT sexuality nonnormative, they also served to reinforce some sexual practices as being illicit. Ultimately, the exhibition opened up conversations about LGBT history and how LGBT people and practices have been defined as illicit and have at the same time resisted such labels.