All thoughtful, scientifically trained people are called to lead at some point in their lives and should be prepared to do so. The STAR Leadership Program is designed to intentionally develop five leadership behaviors (Collaborative Work, Interpersonal Communication, Problem Solving, Foresight and Planning, and Moral Consciousness) amount undergraduate STEM students. The curricular component of the program integrates intentional instruction on leadership theory and activities to promote the development of leadership skills in existing science courses. By having multiple opportunities to learn and practice these skills within different disciplinary contexts, and at different levels of instruction, students are given opportunities to develop their awareness, abilities, and commitment to leading others. Thus far, leadership instruction has been integrated into 25 courses from within biology, chemistry, environmental studies, and physics, ranging from introductory to advanced course levels. Behavior competencies are directly assessed using rubrics that were developed for all five leadership behaviors, derived from the AAC&U VALUE Rubrics, and modified to fit the needs of the STAR Leadership Program.