Using Constructivist Grounded Theory (CGT) and reflexive Thematic Analysis (TA) methods, the purpose of this case study was to construct theory about equity for students studying chemistry at public universities in Colorado. Interviews with students (N=12), chemistry instructors (N=9), and equity practitioners (N=9) as well as observations of chemistry classes (N=42) were collected. Along with these interview transcripts and in-class observations, surveys completed by participants were also included as data. Journal entries of a reflexive or memoing nature were written as part of the data analysis procedures. With these data, I explored potential methods of equitable change in chemistry instruction at public universities in Colorado. Overall, twenty theoretical concepts were constructed using the data to address the research questions. The connections and relationships among these concepts make up the theory of equity in chemistry instruction that was constructed. A theory of equity in the context of chemistry instruction could be the basis for instruments such as an equity observation protocol or surveys to measure equity in chemistry courses. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]