Ranks of Professors and The Path to Becoming a Professor

Professors vs. Lecturers

Professors are scholars that are experts in their field and teachers of the highest rank. They almost always have a Ph.D., perform research in their discipline, and supervise graduate students. Professors may receive tenure (see below) and have job security after doing so. The job of a professor involves many obligations, which are usually grouped under the headings of Research, Teaching, and Service. (See here for a more detailed description of the job responsibilities of professors.) In the mathematics department at UH, professors usually teach one or two courses per semester.

Lecturers, unlike professors, are individuals hired by the university solely to teach. They usually have a Masters degree, but often do not have a Ph.D. In the mathematics department, lecturers usually teach courses prior to calculus, and a few of the freshman-level or sophomore-level mathematics classes. Junior-level and Senior-level mathematics courses are typically taught only by professors, and graduate courses are taught exclusively by professors. Lecturers cannot receive tenure and they often work on year-to-year contracts. Lecturers are also often paid less than professors. In the UH math department, a lecturer will typically teach three or four courses per semester, and their job does not involve any research or service responsibilities. At other universities, lecturers are sometimes called "Adjunct Faculty", "Instructors", or "Instructional Faculty".


After many years of accomplishment in research, teaching, and service, a professor may receive tenure. Tenure is a contractual right to a job, and essentially provides the professor with job security. A professor with tenure cannot be fired or let go from their job unless they are in violation of university rules and the university proves "just cause". Professors with tenure basically cannot be fired --- however, there is also no guarantee they will receive annual raises or other accommodations. Tenure exists to provide senior scholars with academic freedom. The idea is that if someone has proven themself through years of exemplary work and top-notch research, while simultaneously becoming an established expert in their field of study, then they have earned the right to make statements, raise questions, or do research that may be controversial or unpopular without the fear of being fired.

The Path to Becoming a Professor

Graduate Students. To become a professor, one must first go to graduate school to earn a Masters degree and then a Ph.D. It typically takes 2 years to earn a Masters Degree in Mathematics and an additional 3 to 4 years to earn a Ph.D. in Mathematics. Graduate students at all levels will often run recitations for large lecture courses or work as graders or tutors for large lecture classes. Graduate students that have earned a Masters degree and are working on their Ph.D. will sometimes teach a class and be the primary instructor. Graduate school in mathematics is a very intense process with a high drop out rate. After earning a Masters degree, students must be accepted to Ph.D. candidacy in order to continue in the graduate program and earn their Ph.D. One requirement to advance to Ph.D. candidacy is to pass a set of very demanding exams known as "preliminary exams" or "qualifying exams". Not all students pass these exams, and those that do not pass all the required preliminary exams cannot enter the Ph.D. program and must leave graduate school. Others at this point may decide a Ph.D. is not for them and choose to leave graduate school for a variety of reasons. Some students who leave graduate school after earning their Masters degree may decide to become lecturers. Others may seek employment elsewhere, such as industry, government agencies, or education.

Postdocs (also called Visiting Assistant Professors). Postdoctoral positions (also called postdocs) are positions that a person takes after receiving a Ph.D. with the goal of obtaining more research experience. While some teaching-focused schools or four-year colleges without a graduate program may hire a fresh Ph.D. into a tenure-track professor position, if one wants to get a job at a research university, such as the University of Houston, one has to complete one or more postdoctoral positions to be qualified. Most of the time, it is expected a person will do a postdoc at a different university than the one they received their degree at to get broader experience. Postdoctoral positions typically last for 2 to 3 years, and once they end the person must find either another postdoctoral position or a tenure-track job. Usually a person completes one postdoctoral position before getting a tenure-track job as a professor, although it is not uncommon to have to do more before being able to receive a job offer. Postdocs are sometimes also called "Visiting Assitant Professors". The term "Visiting" is meant to indicate the position is not permanent and not tenure-track, and their contract will end in a few years.

Professors. Professors are tenure-track or tenured faculty. In the United States there are three ranks of professor: Assistant Professor, Associate Professor, and Full Professor. (In other countries the rankings may be different, and sometimes similar terms in other countries have different meanings.)

What does this mean for you as a student?

In the United States, the term "Professor" can be confusing because it is used to mean three very different things:
  1. Anyone who teaches a college class.
  2. A tenured or tenure-track faculty member who is at the rank of Assistant Professor, Associate Professor, or Full Professor.
  3. A faculty member at the rank of Full Professor.

When you address the person teaching your classes, it is probably best if you refer to them a "Professor So-and-So", even if you do not know their exact position. This has the least chance of being offensive or insulting. You should never call your instructors by the title "Mr. or Ms.". Always use the title "Professor" or "Dr.".

If you need letters of recommendation or academic advice (e.g., what classes you should take, whether you should consider going to graduate school and how to prepare), it is better that you talk to a faculty member who is an Assistant, Associate, or Full Professor rather than a Lecturer, Graduate Student, or Postdoc.

If you do not know the position or rank of the person teaching your class, you can find out on the mathematics department website. Almost every professor will list their rank on their website, and it will also be listed in their Curriculum Vitae (CV).

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