After partner opens 1NT, we have a good structure for using our bids efficiently to describe our hand to partner. But when the opponents interfere in our auction, we lose some of this valuable bidding space and need to change our approach in order to deal with their interference.
(541) NT Bidding: DONT and Meckwell
(524) Fits and More: Raising Partner in Competition
One of the most important parts of bridge is raising partner. We try to raise Opener whenever possible. We may choose not to support partner immediately if we feel we have something more pressing to communicate, in which case we can respond in our own Major, use a negative double, or bid some number of notrump, but in general we strive to “support with support.”