from more than 40 disciplines. The Association of National Teaching Fellows (ANTF) promotes innovation and supports the sharing of best practice. National Teaching Fellows automatically become a member of the ANTF. The Committee of the Association of the National Teaching Fellows (CANTF) organises the ANTF's work and is the official voice of the association. United States In the U.S. a teaching fellow has several possible meanings: An alternate term for a graduate teaching assistant A graduate teaching assistant whose degree program requires them to teach. A graduate student fellowship whose responsibilities include but are not limited to teaching. An advanced graduate student who serves as the primary instructor for an undergraduate course. Known as teaching fellows at many private universities, such as Harvard University, Boston College, and Boston University, they are also referred to as graduate student instructors (GSIs) at some other universities, such as the University of Michigan and the University of California system. Typically, TFs teach courses in their area of research specialty, in which they hold a master's degree or equivalent. Teaching fellows differ from teaching assistants in that they are responsible for all aspects of the course, including lecture, whereas TAs assist the instructor by performing ancillary course-related tasks such as grading and holding discussion section or laboratory. Many (about two-thirds) of the graduate students who have served as TAs serve as a TF for one or more classes each semester. Although TFs are fairly autonomous in their duties, many universities, such as the University of Pittsburgh, require supervision of TFs by professors experienced in teaching the course content, with whom TFs must hold regular meetings and receive feedback about the quality of their teaching. As a general rule, TFs receive a higher stipend than TAs in accordance with the greater responsibility and time commitment of a teaching fellowship, but like TAs, their contracts are renewed on a semester-by-semester basis, and they cannot be granted tenure. However, many state universities, such as Florida State University and the University of Florida, do not use the title "teaching fellow", and "teaching assistants" are the sole instructors of many classes. They are not required to have a master's degree, and do not usually teach in their area of research specialization, but rather introductory courses in such fields as English Composition (writing) and foreign languages, in which class size must be limited, large lectures are impractical, and multiple "sections" of