In most countries on the European mainland, such as Germany, France, Spain, Italy and the Scandinavian countries, the usage of professor as a legal title is limited in much the same way as in the Commonwealth countries, i.e. it is reserved for someone who holds a chair.

In Spanish-speaking Latin America, the term professor (profesor) is used for any one who teaches at a school, institute, technical school, vocational school, college, or university, regardless of the level of the subject matter taught or the level or ages of the students. This includes those teaching at the grade/elementary school, middle school, and high school levels. However, when the professor teaches at a university, they are specifically called a "university professor".

In addition to people holding the proper academic title, universities in many countries may also bestow famous artists, athletes and foreign dignitaries with the title honorary professor, even if these persons don't have the academic qualifications that normally would be needed for a professorship. However, such "professors" are usually not expected to do any academic work for the university in question.

Professors are qualified experts who may do the following:

The balance of these six fields of professorial tasks depends heavily on the institution, place (country), and time. For example, professors at highly research-oriented universities in the U.S., and Canada, and, as a general rule, in European universities, are promoted primarily on the basis of their research achievements as well as their success in raising money from sources outside the university.

A tenured professor has a lifetime appointment until retirement, except for dismissal with "due cause". The reason for the existence of such a privileged position is the principle of academic freedom, which holds that it is beneficial for state, society and academy in the long run if learned persons are free to examine, hold, and advance controversial views without fear of losing their jobs. Tenure allows professors to engage in current political or other controversies. Critics assert that it also means that lazy or unpleasant professors cannot be forced to improve, and have suggested including management techniques from the business world such as performance review, audits, and performance-based salaries. However, in most cases, individuals enter academia because they are intrinsically interested in the work (professors could generally earn much higher salaries in industry if they so desired), and so they are very unlikely to use tenure as an excuse to withdraw from their research responsibilities. In fact, even in cases where there is no mandatory retirement, many professors continue to be active researchers. However, tenured professors may be more prone to neglecting their teaching duties, if they lack interest in pedagogy.

The argument has also been made that the tenure system actually diminishes academic freedom, as it forces all those seeking tenured positions to profess to the same views (political and academic) as those deciding who is awarded a tenured position. For example, according to physicist Lee Smolin, "...it is practically career suicide for a young theoretical physicist not to join the field [of string theory]." While it is true that after receiving tenure, the academic is free to pursue other theories, the degree of preparation and specialization required before being able to make a meaningful contribution to such theories and the lengthy period of time before tenure is granted means that the academic will be severely handicapped in contributing to any parts of their field other than the dominant paradigm. This is even more so now that many academics are being forced to spend several years in non-tenure track positions before beginning the 5-6 year process of gaining tenure.

In many countries in Europe and in New Zealand and Australia no academic institutions award tenure;[citation needed] in most, whether tenured positions are available varies from faculty to faculty and from institution to institution.

The term "professors" in the United States refers to a group of educators at the college and university level; in Canada, where a major distinction is made between college- and university-level education, the term is generally restricted to universities. In colloquial language, usage of the term may refer to any educator at the post-secondary level, yet a considerable percentage of post-secondary educators do not hold the formal title of "Professor", but are instead lecturers, instructors, and teaching assistants.

These full-time faculty members engage in both undergraduate and graduate teaching, mentoring, research, and service. Only faculty in these positions are eligible for tenure.