Equity assistance centers (EACs) have played key roles in fulfilling the legacy of the Civil Rights Act by providing technical assistance (TA) to districts and schools in addressing discriminatory behaviors on the basis of race, ethnicity, gender, and religion for over 50 years. In 2002, the National Center for Culturally Responsive Education Systems (NCCRESt) was federally funded as an EAC offering a new model of TA. In a mere seven years, the NCCRESt played a pivotal role in shifting the discourse and efforts to address disproportionality. In this article, we provide an historical contextualization of policies and research that converged to shape the NCCRESt’s TA, reframing and producing new forms of critical evidence on the racialization of disability and the required responses to tackle this long-standing equity problem. We close with reflections on the promises and possibilities of building on the NCCRESt’s disproportionality legacy.