Most of Felix Gonzalez-Torres's stacks of paper are designed to be depleted; viewers can take away one of the printed broadsheets that bear photographic images or oblique texts. Though reminiscent of minimal forms, these works initiate a dynamic interaction with the public. “Untitled” (1991), however, structures this interaction in a more subtle, reflective way. The work is a unique stack of 161 signed and numbered silkscreens that remain together. Originally presented in the form of a 1989 billboard commemorating the 20th anniversary of the Stonewall Rebellion, its iteration as a stack of prints was meant, as the artist noted at the time, as a “more private and personal object”—one that is not disseminated physically but instead through the experience of remembering. The stark black page and white typeface on each sheet trace a nonlinear chronology of significant events in the history of the gay-rights movement. From the election of Harvey Milk as Supervisor for San Francisco to one of the largest civil rights marches on Washington, D.C., “Untitled” creates an open narrative of dates, names, and places that evoke the collective memory of an ongoing struggle.