[Stephen Tu]

I can't seem to find a lot of info on this, a lot of sources seem to say "new suit in response to weak two is forcing", but then don't describe exactly what opener's rebids ought to mean.

opps silent, 2♠-3♥-?
Define:
3nt/4♣/4♦
?

[awm]

What I use is:

3NT = sort of scattered values, usually short in pd's suit
new suit = side values in this suit with a good hand (like feature)
raise = could be doubleton support, esp. Hx or with a side singleton
rebid suit = a decent suit, tends to deny side values

[aguahombre]

Depends on the discipline of the 2♠ bid to begin with. Since our weak two's are strength-concentrated, the responses are strictly based on amount of support for the new suit.

NT=2
♠ rebid=one or zero
raise=3
new suit(cue)=feature with 3 in responder's suit (might be a stiff in the cue suit).

[Siegmund]

Over 2S-3H, a method like aqua's looks very sensible.

Over 2 of a major, there is room for a bit more exploration, and with an unknown partner I would assume that a new suit denies a fit but shows a feature, returning to 3 of my own suit is a minimum with no fit, raising partner shows Hx or xxx or better. I'd avoid jump shifts to 4 of a minor with an unknown; with my reg p I play them as splinters in support of responder's suit. I can imagine someone else playing them as cues.

[Free]

I usually play 4m as cuebid with ♥ support, otherwise rebid your own suit. 3NT can be used to show a doubleton support exactly and a poor suit of my own.