Mentorship is an activity in which science, technology, engineering, mathematics, and medicine (STEMM) professionals engage to help develop the next generation of STEMM professionals. While that statement may be a truism, it does not adequately address three important questions: What exactly is mentorship? What makes it effective? How does it occur in various settings? Mentoring relationships can be intentionally created and developed, and there is a substantial scholarship—a science of men...