What do you respond to a 1-of-a-Minor opening with 4-card support and no 4-card major?
I'm assuming some form of Standard American/French/German with 5 card majors and strong NT.
Playing the most common form of inverted minors:
With &lt;10 points, 1N (but I would consider a tactical 3D with S:x H:xxx D:KQxx C:xxxxx)
With 10+ points(*), 2D with diamonds and a small doubleton or singleton in a major, and usually NT otherwise(**).
Not playing inverted minors, I think any non-forcing raise with 4 cards is usually problematic, but if you're playing forcing jump raises, 3m with 4 works.
(*) Experts seem to be switching to 2m being game forcing, with invitational hands bidding an artificial 2S or 2N or 2D(for clubs) or 3C(for diamonds).
(**) There are some advantages to making 2N forcing, in which case you have to bid 2m with 4 card support and 10-12 points.