Making your bid is worth 40 or 50 points. Setting the opponents is often the same size swing in the other direction — plus it denies them what they were counting on. Playing defense is not passive; it's an active hunt for the one book that breaks their contract.
Identify their required books
Add up their team bid. Say they bid 3 and 4 — that's 7 books. They need 7 out of 13. That means you and your partner need to take 7 of the 13 to set them (assuming they're not shooting for bags).
Every book you deny them counts double: it's a book you took, and it's a book they didn't. Set them and it's a 100-point swing (their bid failure + your bid success).
When to press
Press when you can see a clear path to setting them — you have the trumps to steal their late books, or their bid is loose and one bad cut ruins it.
Press when the score demands it. Setting them is a way to close a deficit without needing a big bid of your own.
When to sit back
Sit back when your own bid is at risk. Trying to set opponents while your team is also going to miss is a way to lose 200 points in one hand.
Sit back when they have overwhelming trump strength. If they bid 8 and clearly have the cards, focus on making your 4 or 5 and taking the smaller win.
The book that breaks them
Watch for the specific book you can steal that costs them the bid. Often it's a middle-round book in a suit where one opponent is short and vulnerable. If you have a spade waiting for it, don't burn it early on a book they were going to lose anyway. Save it for the kill.
