"Mentoring" comprises multiple activities and relationships. Asking the supervisors of postdocs to provide mentoring is not unreasonable. Like any good learning process, however, mentoring is best and most readily accopmlished when there are clear learning objectives. Postdocs can help develop their own mentors by working toward articulating their needs and desired learning objectives, asking their supervisors to undertake specific roles and responsibilities in that process, and assuming responsibility themselves for ensuring that the mentoring process stays on track once a set of objectives is mutually agreed upon as appropriate and accomplishable. In addition, postdocs (and everyone else) should recognize that it's unlikely that any one individual will be able to provide the sum total of mentoring that might benefit a protege at any given point in time. As a result, people benefit from having multiple mentors, or what some researchers and other experts have termed a "mentoring network." Ideally, one's mentoring network will include those within one's own organization -- "internal mentors" -- who can provide needed information, advice, and guidance specific to that particular environment and its people, practices, policies, procedures, and politics. But it will also include those external to one's own organization, who are in a position to confirm standards that cut across insitutional variations. External mentors often serve as safer confidants, without the added complications of secondary roles such as advisors and supervisors, who will be evaluating the protege's performance as well as providing guidance. (MentorNet (www.MentorNet.net) is one online, large-scale, nonprofit service for science and engineering fields, which enables postdocs to locate and be matched with external mentors in their fields. While there are still too few volunteer mentors to serve all the postdocs who may be interested, a growing number of postdocs each year have found external mentors through MentorNet -- 136 in the last year alone.)