This chapter defines the phrase “Transgender Exigency” as a situation marked by an urgent need; in this case, to address the definitional challenges evinced by the need for transgender rights. The chapter provides evidence for substantial prejudice against transgender people, as well as the dramatic increase in transgender visibility in the 2010s. The collision of prejudice and visibility has led to a series of controversies that involve regulatory definitions, some of which are the subject of Part II.