Academic rank in the United States
Academic ranks in the United States are the titles, relative importance and power of professors, researchers, and administrative personnel held in academia.
For regular faculty (i.e., not counting administrative positions such as chairmanships or deanships, nor positions considered "staff" rather than faculty), the descending hierarchy in most cases is:
Somewhat outside the regular hierarchy:
[Note that while "Professor" as a proper noun (with a capital "P") generally implies a position title, the common noun "professor" in the US appropriately describes anyone teaching at the college level, regardless of rank; also, as a prenominal title of address, it can be capitalized without implying the title rank. Also note that "Professor Emeritus" does not generally denote a title of special distinction; in this context, emeritus merely means a faculty member who has retired in good standing, and can be applied to most ranks.]
Traditionally, Assistant Professor has been the usual entry-level rank for faculty on the "tenure track", although this depends on the institution and the field. Then, promotion to the rank of Associate Professor and later Professor (informally, "Full Professor") indicates that significant work has been done in research, teaching, community service, etc.; in some institutions the associate level indicates that a tenure-track professor has been granted tenure. It typically takes about six years or so to advance in rank. The time for advancement between associate to full professor is less rigid than for assistant to associate. Typically, failure to be promoted to associate professor from assistant results in termination following a 1-year appointment. Professors can remain at associate level more-or-less indefinitely at most institutions even if they are not promoted further.
Traditionally for "professional" fields such as engineering, law, medicine, business, or management - and lately expanding to others - faculty types can also include Clinical Professor or Professor of Practice. These ranks are generally not tenure-track and emphasize professional practice knowledge & skills rather than scholarly research. Likewise for the less-common title of Teaching Professor, which is not limited to professional fields. Recently, some institutions have created separate tenure tracks for such positions, which may also be given other names such as "lecturer with security of employment".
Other faculty who are not on the tenure track in the U.S. are often classified as Lecturers (or more advanced Senior Lecturers) or Instructors, who may teach full-time or have some administrative duties, but have no research obligations (essentially the converse of "research-only" faculty or "research-only staff", which has no true counterpart because teaching positions are almost always "faculty" - except for student-assistantships), which also come in various forms and may be either tenure-track or not. Both Lecturers and Instructors typically hold advanced graduate/professional degrees. The term "professor" as a common noun - as well as "Prof." as a prenominal form of address - may be used for persons holding any kind of faculty position; however, the prenominal title of "Dr." is reserved exclusively for those who have obtained doctoral degrees (typically a Ph.D. in academia, in contrast to the more common use of "Dr." in the general public for physicians holding an M.D./D.O.). In academic medicine, Instructor usually denotes someone who has completed residency, fellowship, or other post-doctoral (M.D./D.O.) training but who is not tenure-track faculty.
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