Little fix in the order: Herr Professor Doktor. But only in formal writing.

When talking to them, it's Herr Professor.

Austria loves their honorifics, though. Every school teacher is a Professor, and the Professor's wife is Mrs. Professor.

Strictly speaking, only Austrian grammar school teachers appointed as civil servants were allowed to carry the title Professor. That appointment (Pragmatisierung) is somewhat comparable to academic tenure: you had a job guarantee and the right to stay at "your" school, whereas non-tenured teachers had to switch schools in case of insufficient work hours. But a tenured teacher had a lower salary compared to a non-tenured one and so emperor Franz Josef had the idea with the additional Professor title. A smart move, because he satisfied the academic "vanity" of the teachers which kept salary costs lower.

Since the difference between tenured and non-tenured teachers is beyond the understanding of 10-18 year old pupils, they called every teacher "Professor".

Small correction: only grammar school teachers are called Professors in Austria, junior high school teachers just "Herr/Frau LehrerIn". In earlier days, you needed a master degree to teach in grammar school and just a bachelor degree for junior high.

*every school teacher after secondary school. Before that they're still mostly "Mr./Mrs. Teacher".

> Every school teacher is a Professor.

Same in Poland! But only for high school.

Definitely cultural! In my undergrad (UK) we called our professors by their first names.

I knew a chem. eng. professor at a university, who I believe had come from Austria, and had "Professor Doctor Engineer" as the title on his doorplate. Very much stood out in the US and it was something students and other faculty would tease him about.