This dissertation traces the development and evolution of disability as a legal concept in California during the twentieth century. It begins by analyzing how disability came to be understood through a medical lens assessing an individual’s capacity to work from the late eighteenth century, through the nineteenth century, and into the early twentieth century.The second chapter shows how the California state legal system joined medical professionals in favoring expansion of private care at the expense of government-sponsored alternatives, while at the same time steering private care toward acceptance of group insurance over traditional fee- for-service. It pays particular attention to cases involving Kaiser Permanente’s group prepayment program as a model for expansion of private health care coverage that continued to exclude those in desperate need of care—the unemployed, those with disabilities, and those with lower incomes. The third and fourth chapters turn to activists and state officials in California to illustrate how disability as a legal concept shifted from an emphasis on work, welfare, and rehabilitation to a focus on engagement, inclusion, and assimilation in all aspects of life through the independent living movement. The third chapter analyzes activists’ efforts to work with and against state officials to change how they were perceived and what opportunities they could pursue. The story of Cowell, Berkeley, PDSP and the Centers for Independent Living is a story of individuals who strove for individual freedom and then entered the halls of state power to steer those same expansions of freedom. The fourth and final chapter reveals how activists could implement their reconceptualized definition of disability into state law through bureaucratic channels. Proud activists-turned- bureaucrats were able to work within the system that they had previously rebelled against to codify their vision of inclusion and assimilation in society through state funding that was necessary for independent living centers to operate. Ultimately, this dissertation analyzes the ways advocates inside and outside of state institutions can alter legal definitions and garner state support.