In the April, 2011 issue of "The Bridge Bulletin", Billy Miller recommends the Dead Notrump Defense in his "The Coolest Gizmos and Gadgets" column.
The defense applies "whenever the opponents have bid one or more suit(s) followed by 1NT and it goes Pass-Pass back to you. (It is not on over a 1NT opening.) Also your side must have been silent in the auction until that point."
"If you now double, the double is penalty oriented and begs for the lead of dummy's first bid suit."
"When we balance with a suit, it shows at least four of that suit and at least four in a higher suit."
"At least one of our two suits must be an unbid suit."
So after (1♣)-Pass-(1♥)-Pass(1NT)-Pass-(Pass):
Double = Penalty Partner "is expected to leave in the double. Partner should pull 1NT doubled only with a super-weak hand and at least a six-card suit".
2♣ = 4+ ♣ and either 4+♦ or 4+♠
2♦ = 4+ ♣ and either 4+ ♥ or 4+ ♠
2♥ = 4+ ♥ and 4+ ♠
The downside of the agreement, as Billy points out, is bidding a hand "that contains a long, bad suit and with values that made you feel uncomfortable about bidding right away. This system gives you the safety of having two suits. Who knows? Maybe DND [Dead Notrump Defense] is saving you from yourself."
Double is penalty, showing strength in one of opponents' suits. Where applicable, it suggests a lead of RHO's suit. The double should be removed by a very weak partner (with less than 5 points and a 6 card suit).
Bid of a suit at the 2 level, instead of doubling, shows 4+ in that suit and 4+ in a higher ranking suit.
Billy reports "both sides of DND have paid off over the years." The Dead Notrump Defense has provided my partnerships plenty of top boards and some match swinging penalties since adopting it in 2011. It is not easy to find the defense on the web. So I wanted to post it here to share it with the Bridge Winners community.