Mentorship is one of the fundamental keys to growth and learning in any field, not just science. But our profession is unusual to the degree in which mentoring is used to guide and develop scientists, especially during the years of graduate school. While the Ph.D. advisor is rarely the sole mentor in a student's life, the success or failure of this relationship can literally make or break a young scientist. Most advisors I talk to believe they do an effective job of mentoring their students. Most students I talk to disagree.