
Reviewed for patch 7.3d

Favorable matchup
Reviewed for patch 7.3d
Against Vayne, Caitlyn punishes her before she reaches her three hits. Put Yordle Snap Trap where Tumble is going to land, fire Headshot at double range on the trapped target and use 90 Caliber Net to get away from the walls where Condemn stuns.
Yordle Snap Trap immobilizes and reveals the champion who steps on it and readies an empowered Headshot. Vayne closes in with Tumble: a trap between your position and hers covers the spot where she wants to land.
Against a trapped or netted target, Headshot's range doubles. That lets you punish Vayne without stepping into the distance where Silver Bolts asks for three hits in a row on you. Since 7.3a, Headshot is 60-90% of attack damage based on level and Caitlyn gains less attack speed per level.
Condemn knocks back and only stuns if the target hits terrain. 90 Caliber Net slows Vayne and knocks you back: use it to open space toward open ground, never toward the river or jungle walls.
Until Vayne has Final Hour, punish her every time she walks up to a minion, with attacks and Headshot. Her window comes when you miss the trap or spend the net; when that happens, back off toward your support.
As Vayne, don't walk straight at Caitlyn: the traps cover the short path. Approach from the side opposite her last trap, keep Tumble to get out of a net and look for the duel once she has used 90 Caliber Net. Condemn is worth more when she's near a wall; otherwise, use it to separate her from her support.

Favorable matchup
Reviewed for patch 7.3d
Condemn is an ability Vayne casts on a target, and Spell Shield blocks exactly that: one enemy ability cast on Sivir. Without the wall stun, Vayne is left with her basic attacks while Sivir pushes with Ricochet and picks when to fight.
Condemn is Vayne's only crowd control and the way she wins duels near a wall. Spell Shield blocks exactly that kind of ability cast on Sivir, and when it does you get health back and a burst of speed: Vayne loses her best opener and you leave faster.
Vayne has no way to contest a wave that clears itself: Ricochet jumps between minions and Boomerang Blade hits going out and coming back. Every wave you push is one she last-hits under her tower, far from you.
Silver Bolts deals true damage on the third consecutive attack or ability on the same target. Fleet of Foot gives you speed when you attack a champion: use it to leave the trade before you take the third one.
Play every wave with Spell Shield available. If Vayne casts Condemn and you block it, you have a few seconds without her stun: that's the moment to trade, or to push and move.
If you're playing Vayne, make Sivir spend the shield before you commit: cast Condemn once she has used it, or use it away from walls just to peel her off her support. Last-hit from angles where Ricochet's bounce can't reach you and don't let her push drag you from your tower into the river.

Execution matters
Reviewed for patch 7.3d
Jhin against Vayne is a race for distance: Deadly Flourish roots her from very far away if she was damaged recently, and with her standing still his four shots hit hard. Everything depends on the root: don't take the long duel without it, least of all during Final Hour.
Deadly Flourish has huge range and stops on the first champion. If Vayne was recently damaged by you, your allies or a lotus trap, she is rooted. One attack from your support or one of your traps is enough to set up the shot.
Captive Audience places an invisible lotus trap that slows and explodes when stepped on. Put it where Vayne walks in to last-hit or where Tumble would land: if she triggers it, she already has the recent damage Deadly Flourish needs to root her.
Whisper fires at a fixed rate and holds only four shots; the fourth is a crit with execute damage. Since 7.3b that missing-health damage reaches its cap at level 10 instead of 15, and standard crit damage goes from 80% to 85%. Against a target that can't move, all four shots land.
You have room as long as Vayne doesn't have Final Hour: invisibility during Tumble lets her close in without you seeing her. With her ultimate up, back off toward your support and wait it out.
Playing Vayne, step out of Deadly Flourish range every time Jhin or his support damages you: for a few seconds, that shot roots you. Go in while Whisper reloads or right after the fourth shot, and use Final Hour's invisibility to approach from the side his traps don't cover.