The goal of this study was to assess the outcomes of a grant-funded intervention designed to provide comprehensive training and support for holistic admissions in 26 STEM PhD programs at five California research universities. This pilot intervention combined a flexible, research-based model of holistic review, training for faculty involved with admissions, and informal coaching in how to critically analyze and redesign their admissions processes. Using a theoretical framework centered on organizational learning as a mechanism of equity-minded change, we assessed evidence of learning in two ways: 1) adoption of admissions practices that align with a new paradigm, and 2) changes in the racial and gender composition of applicants, admits, and enrollees. Drawing on administrative and survey data from participating programs, we find evidence suggestive of positive, sustained changes in both adoption of new admissions practices and racial diversity. This indicates that systemic, scaffolded approaches may promote more equitable processes and outcomes in the graduate and professional education context.