This project aims to serve the national interest by improving students’ abilities to reason logically, think critically, and solve complex problems. It will identify instructional strategies for introductory proofs courses that empower students to analyze and solve important problems in advanced STEM settings. This is a two-phase project for which phase 1 included a cyclical approach to investigate student reasoning and to design and study research-based instructional tasks that evoke and address challenges in the teaching and learning of foundational ideas. Efforts from phase 1 had an immediate impact on every Virginia Tech mathematics major, including pre-service teachers preparing to teach secondary mathematics. In phase 2, project outcomes were disseminated and used to support introductory proofs instructors nation-wide as they optimize instruction for facilitating students’ development of robust logical reasoning, critical thinking, and overall success in the STEM arena.