Mentor was the man Odysseus entrusted with the care and education of his infant son, Telemachus, as he was leaving Ithaca on what would be a 20-year absence to fight in and slowly return from the Trojan war. The role of mentor thus implies guiding the maturation and development of the person being "mentored."

The mentoring of junior scientists (students and post-doctoral fellows) is one of the most important obligations of senior scientists at the National Institutes of Health (NIH). Scientific mentoring has several important goals: teaching an approach and methodology for scientific investigation, developing a sense of what questions are technically able to be answered and have important answers, transmitting a history of ideas in a discipline including identification of major contributions and contributors, encouraging the development of the ability to evaluate critically the quality of one's own and others' research, providing an ethical framework for the conduct of research and dealing with collaborations, enhancing the development of oral and written communication skills, and facilitating entrance into the research community in the discipline. In addition, the mentor is expected to assess the progress of the junior scientist, make suggestions for improvement on a regular basis, and provide advice and counsel regarding career development decisions. Mentoring may be obtained by the fellow from others, as well.

Mentoring is a practitioner-apprentice relationship, and by its nature, requires interaction between them. According to a survey of post-doctoral fellows conducted at the NIH, a subset of fellows interact with their mentors less frequently than once a month and some reported never having had a discussion about career development. Disturbingly, women reported these conditions significantly more frequently than did men. While the nature of mentoring relationships can vary widely, the NIH Scientific Directors consider the following guidelines as the minimal requirements for effective mentoring.

1. The mentor (or a surrogate when the mentor is on travel) should be readily available to the trainee to answer questions about research and discuss results and future research directions; this availability implies responding within 24 hours to specific inquiries initiated by the trainee and meeting in person with the trainee (either alone or with other laboratory staff) at least every 2 weeks.

2. The mentor should work closely with the trainee in the preparation of oral presentations of the research and the preparation of papers and abstracts describing the work.

3. The mentor should advise the trainee about the best fora for presenting the research work and when attending meetings together, the mentor should strive to introduce the trainee to important contributors to the research field.

4. On an annual basis, the mentor should provide the trainee with an oral and written assessment of the trainee's progress, strengths, and areas requiring improvement. This meeting should include a discussion of the trainee's professional goals and the mentor's feedback on their appropriateness, the likely length of stay in the laboratory, and planning and preparation for career decisions after the NIH training.