Declarers learn to finesse against their opponent’s honors. It is wise to remember your opponents can finesse against in your honors. To protect your honors, try to avoid letting an a defender who can lead through your honors gain the lead. This tactic is called an Avoidance Play. 
The hand to the right illustrates an Avoidance Play. West leads the ♠5, their 4th best spade, against 3NT. Dummy (North) plays the ♠8. East plays the ♠9, lowest of the touching 10-9. Declarer wins the ♠Jack. Since the 3rd hand playing to a trick will typically play their highest card (or lowest of touching high cards), Declarer places West with the ♠Ace-Queen. If East gains the lead, East can lead a spade to finesse South remaining ♠King. This makes East the Dangerous Opponent. South wants to keep East off lead.
Declarer has won a spade trick and have 7 quick winners: ♥AKQ ♦AK ♣AK. This brings declarer to 8 tricks. Declarer would like to get an additional diamond trick without letting East gain the lead. Declarer has a 2-way finesse against the ♦Queen. Declarer chooses to finesse against East for the ♦Queen to ensure East doesn’t gain the lead. Here, West has the ♦Queen and declarer wins 10 tricks. Even if West had the ♦Queen, finessing against East ensures 9 tricks.
The following board illustrates a Hold Up play combined with an Avoidance Play.
W
est leads the ♠King, top of an honor sequence, against 3NT. East-West has 8 spades between them. If the spades break 4-4, declarer will lose just 3 spade tricks. If spades break 5-3, declarer can hold up their ♠Ace until the 3rd round of spades to cut defensive communication. Declarer has 8 quick winners: ♠A ♥AKQ ♦AK ♣AK. The hearts are blocked, but declarer can afford to cash the ♥King-Queen to unblock the suit.
Declarer has a 2-way finesse for the ♦Queen. The “8 ever, 9 never” adage suggests attempting to drop the ♦Queen. If West has ♦Qxx, as shown, cashing the Ace-King will allow West to beat 3NT with 4 spade tricks and 1 diamond trick. Declarer prefers to finesse against West for the ♦Queen to keep West, the Dangerous Opponent, off lead. Here, West has the guarded ♦Queen. Finessing against West allows declarer to win 11 tricks.
