[Fluffy]

all vulnerable, LHO deals and opens 2NT (20-21), passed to you

you've got:

♠QJ8742
♥AKQ108
♦-
♣83

What do you bid if you have no agreements?

What do you bid in your usual partnership assuming partner will not do any encouraging moves himself?

[Free]

Dbl

[dake50]

Dbl. Partner knows this is not a casual bid,
but some playing strength.
[directly opposed to the double that says
declarer must play one-handed - bet he can't].
I do keep my NT-takeout bids over 2NT
just for this great distribution type of hand.
I make my M+M bid and hope partner can see 1 trick for game.

[hrothgar]

All me a wimp, but unless I have a bid that shows both majors, I'm going to pass.

Double scared me a LOT
Partner is almost certainly broke
There is a decent chance that he has a long diamond suit and the LAST thing in the world that I want is to hear partner bid 3♦

[han]

Partner is almost certainly broke? They just passed out 2NT!

[cherdano]

I would take double as penalty without discussion.

[MrAce]

Neither DBL nor Pass would occur to me. If i don't have a way to show majors i am bidding what i have and that will be my longest suit.

To me its a matter of 3 or 4♠, without ♠T i will go with 3♠. After all we are not balancing a weak 2. This is not like bidding 3♠ over 2 NT in 2nd seat which could have preemptive values, they sit on 2 NT and we are reopening, pd knows i have a huge playing potential.

[whereagles]

you can play DONT over 2NT. That would give you an easy 3H bid

[gnasher]

3♠. We expect partner to have about 6 HCP, and there's no reason to expect either that it's all working or that he has a fit. If he has something like Kx xx Kxxxx xxxx, 3♠ will be high enough.

[Fluffy]

MrAce, on 2011-April-19, 14:35, said:

This is not like bidding 3♠ over 2 NT in 2nd seat which could have preemptive values, they sit on 2 NT and we are reopening, pd knows i have a huge playing potential.

I missed this point completelly, now I am convinced that 4♠ is very bad .

partner had ♠xx ♥x ♦Kxxxx ♣Qxxxx, my LHO doubled 4♠ for -200 wich was worth only 6% MPs

[cherdano]

gnasher, on 2011-April-20, 00:39, said:

3♠. We expect partner to have about 6 HCP, and there's no reason to expect either that it's all working or that he has a fit. If he has something like Kx xx Kxxxx xxxx, 3♠ will be high enough.

There is another point. Since LHO is balanced, his honors are more likely to be in spades than in diamonds, and thus conversely partner's honors are more likely to be in diamonds than in spades.

[Yu18772]

Without agreements I would take dbl as penalty. By default I usually play the same system over 2NT as over 1NT (with adjustment to hand requirements)