This $1,199,915 Project Grant award from the National Science Foundation's STEM Education program (CFDA 47.076) aims to improve the culture of teaching in STEM departments at institutions of higher education. The project will provide a two-year professional development experience for approximately 50 STEM faculty, teaching assistants, and instructors at Middle Tennessee State University over 5 years. The goal is to promote a collaborative, inclusive, and growth-oriented teaching culture through the "TRIOS" professional development model, which is grounded in strength-based reflexivity. The project will generate six case studies, produce a handbook for stakeholders, and develop an empirically-based model for advancing teaching cultures in STEM departments. This work is intended to better support the needs of a diverse student population in STEM fields.