Basically this is someone who was a master in their field, but they're now behind the times as they haven't been able to keep up with advances in the field. Particularly using newer technologies. This can be done in three ways: This is, of course, Truth in Television. Professionals in many fields must constantly undergo training to keep up with the state-of-the-art. Could result in or be a result of Surpassed the Teacher. Examples of Obsolete Mentor include: