Amputation need not always signify castration; indeed, in Jack London’s fiction, losing a limb becomes part of a process through which queerly gendered men become properly masculinized. In her astute book, Vulnerable Constitutions, Cynthia Barounis explores the way American writers have fashioned alternative—even resistant—epistemologies of queerness, disability, and masculinity. She seeks to understand the way perverse sexuality, physical damage, and bodily contamination have stimulated—rather than created a crisis for—masculine characters in twentieth- and early twenty-first-century literature.   Barounis introduces the concept of “anti-prophylactic citizenship”—a mode of political belonging characterized by vulnerability, receptivity, and risk—to examine counternarratives of American masculinity. Investigating the work of authors including London, William Faulkner, James Baldwin, and Eli Clare, she presents an evolving narrative of medicalized sexuality and anti-prophylactic masculinity. Her literary readings interweave queer theory, disability studies, and the history of medicine to demonstrate how evolving scientific conversations around deviant genders and sexualities gave rise to a new model of national belonging—ultimately rewriting the story of American masculinity as a story of queer-crip rebellion.