What are secondary "visiting" positions? Note that I'm not talking about &quot;visiting professor&quot; or &quot;visiting lecturer&quot; positions in the US, which seem to be full-time non-tenure-track positions offered at some US universities.
What I mean is that I sometimes see people list &quot;visiting researcher&quot;, &quot;visiting scholar&quot;, or &quot;visiting professor&quot; as their second affiliation, and seemingly they are not actually being paid by the second institution (their full-time position is at their primary place of employment) but they simply maintain a second affiliation through this visiting position. Often I see people having visiting affiliations at universities in other countries, or professors keeping a visiting position at their previous place of employment after they moved to another place.
What are these visiting positions? How does one get it, and what is the point?
A typical reason for these positions is that a person needs a formal affiliation with the &quot;visited&quot; university for some formal reason. This is particularly common for visiting positions at past institutions. These can be there to faciliate continued supervision of PhD students at the old instituation, or to keep existing grants. Grants can be a reason beyond this - eg by having a visiting position at some university, it may become possible to get travel there (or even to other places) paid for by a grant situated at that university.
In the short-term visiting positions can actually be just what they are called. The person may in fact visit the instituation for a while, sometimes with funding from the host institation (which would be acknowledged via such an affiliation). It can also be something mundane as needing some formal association with the host university to get a keycard or library access.
I assume that almost always the person receiving a visiting position will have a pre-existing strong relationship with either the institution or an academic at that place. There will be some formalities depending on the institution, but that is something people figure and sort out once the need arises.