Endometriosis is a common gynecological disorder that can cause chronic pain and infertility. To better understand mechanisms of disease etiology and progression, researchers are increasingly turning to model systems. In vivo approaches have notable limitations, including limited ability to model human anatomy-related pathologies and poor translation of therapeutics developed in animal models. This chapter describes the current body of work surrounding the recent emergence of in vitro models of endometriosis. This work aims to describe methods by which researchers can consider specifying their work to stages of disease, lesion location, and interactions that could drive disease progression. This chapter defines a roadmap for the development of more robust and specific models of endometriosis with the goal of realizing translatable therapeutic strategies and noninvasive metrics of disease presence and progression.