The EURO WISDOM Forum provides a platform to support, empower and encourage the participation of all genders in Operational Research within EURO. You'll find more details about the EURO WISDOM Forum here: https://www.euro-online.org/web/pages/1654/wisdom
Operations research is a very vital and critical option in Mathematics, to the best of my knowledge. I have a colleague whom is majored in this area. However, it's also a vital part of social science and management in most schools in Nigeria.
I will conclude here that, depending on the curriculum design, most course outline in Statistics/Mathematics major in Operations research or Mathematical modeling. Engineering on the other hand, especially process fields also cuts across this area as an analytical tool to solving problems.
Operation Research(OR) is a core part of mathematics ,but some engineering subjects like industrial engineering has co-relation with OR. Many theories of OR are used in the field of engineering to optimize production cost ,maximizing profit and reducing the use of resources .
Currently, the percentage difference between affiliation to Engineering and Business Schools seem to be not very wide and I think this is OK: probably, this shall also be looked at from a country perspective (e.g., there are countries where OR seems to be more affiliated to Engineering rather than Business Schools)
Euro Excellence in Pratice Award (2018), a competition in Operational Research