Librarians providing individual information instruction need to be able to quickly and accurately assess the student's level of experience and ability and to offer the correct balance between support and challenge. Paul Hersey's Situational Leadership Model can provide librarians with a cognitive framework for assessment; it helps the instructor to use techniques based on his or her assessment of the student's ability, thereby making instruction more learner-centered. In the Situational Leadership Model, one's leadership or teaching style is determined by the client's ability, and follows a progression through four quadrants, representing the student's developmental level and the appropriate leadership style. In the first quadrant, the instructor must provide high support and direction in order to help the inexperienced student move to the next stage. The second quadrant consists of the student who is ready to be an independent learner, but is unable to because he or she is in the process of developing the necessary skills. The quadrant three student needs low direction from the librarian, and occasional support as subject matter becomes more difficult. The quadrant four group consists of faculty members and students who have reached the goal of independent library user. In this paper, situational leadership theory is used to discuss how to assess the experience and developmental stages of adult learners, hearing-impaired students and students for whom English is a second language. Student characteristics and supportive behavior of the instructor are charted. (Contains 35 references.) (AEF)