Closing equity gaps in student outcomes has been a key part of the national agenda in postsecondary education the last two decades as goals to increase the number of college graduates coincides with an increasing number, and future majority, of students from historically marginalized communities. Impactful support programs for students from marginalized communities are critical but remain predicated upon students adjusting to fit organizational practices and policies not designed for current students. This research focuses on faculty as the critical, leading agents of change in postsecondary education for closing equity gaps, given they shape the academic structure of their institutions and deliver the core services of the educational experience. Key tools of change include definition and measurement--what are we seeking and how will we know where we are? This study develops both a conceptual model of equity from a transformative perspective, called the equity ethos model, and a corresponding survey called the Equity Ethos Instrument (EEI). The equity ethos model is comprised of six dimensions: antiracist, identities-conscious, humanizing, institutionally accountable, reflective/reflexive, and whiteness-norms aware. Each dimension is assessed along a continuum of multidirectional phases, seeking to understand how faculty are orienting to equity in their Awareness, Knowledge, Values, Practices, and Advocacy. An instrument for one dimension--Institutionally Accountable--was developed and validated with a national sample of 493 faculty members. Confirmatory factor analysis was used to confirm the model and to create a parsimonious instrument. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]