Leads against part scores (NT) by Matthias Huberschwiller

A: J♠ - You must not lead your longest suit here, but a Spade, which is a lot less dangerous.
You or your partner will get on lead many times, and it's better if he's the one who plays Hearts first.

Your result so far:

A: 3♠ - You won't lead your doubleton, or Clubs. How do you choose between Diamonds and Spades?

Just look at the bidding. South didn't open a major, so he doesn't have a 5-card suit there, but he can have a 5-card minor.
North has not used a Transfer, so he has no 5 card-major either, but he can also have a 5-card minor.

These are reasons why you should prefer to lead a major instead of a minor.

Your result so far:

A: 10♣ - Even though it's dummy's suit, a Club is the best choice of lead.
Hearts is South's suit so that's too risky, so is a Spade, which has a big risk of setting up a Spade trick in dummy.
A Diamond away from the Ace is nearly certain to give up a trick.

A Club is not that dangerous, since you have a sequence, and your partner's honors are going to be behind dummy's clubs. Remember that North can have as few as 3 clubs.

Your result so far:

A: 8♠ - Your 5-card suit is the same as declarer's, you must lead an other suit.

You need to choose between Diamonds and Spades.

When South bid 1 NT, he denies a Heart fit, but also four Spades. He must have a hand with the minors. Your partner rates to be long in Spades rather than Diamonds, so you must lead the 8 of Spades (Top of Nothing).

Your result so far:

A: 9♦ - South has 4 Hearts, but since North used Stayman, he has 4 Spades. Leading a major is too dangerous. The only option is the Top of Nothing 9 of Diamonds.

Your result so far: