[hv=n=skqjtxxhakxdaxxcx&s=sahqtxxdkjxxxckqx]133|200|Scoring: ????[/hv] Playing Fantunes I got to hold this hand in South. Since the auction likely should not be different from any other natural system I decided to post it here. Partner opened 1♠ and I responded 2♦ (GF) and the bidding went on 2♠-3♥-4♦, without knowing partner's extra strength, I now decided that 4♠ would be the place to play, but partner continued 4NT (showing slam interest and even keycards), we ended up in playing 7♦, which went down a lot. Of course 6NT was a laydown and we would have reached it easily, but I assumed that spades were the agreed suit and partner that diamonds and that lead us to wrong tracks. Most of the problems would not have been there of course if I had bid 2NT or 3NT instead of 3♥, but.. My question is, that are there any general rules, when the suit is agreed and cuebidding starts? For example, does 1♠-2♥-3♥-3♠ show spades or is it a cuebid? What about 1♦-2♥-2♠-3♥-4♦?