Gin Rummy is the two-player version of Rummy, tightened into something much more tactical. You never lay melds down during play - you hold everything hidden and decide when your hand is tidy enough to end the round. Knowing when to stop is the whole game. A round takes about 5 minutes.

What You Need

Players: Exactly 2.
Deck: One standard 52-card deck. Aces are low.
Extras: Pen and paper for scoring.

Key Terms

Meld: A valid group of cards - either a set or a run.
Set: Three or four cards of the same rank.
Run: Three or more cards in sequence in the same suit.
Deadwood: Cards in your hand not part of any meld, and the points they carry.
Knock: Ending the round by declaring your deadwood is 10 points or fewer.
Gin: Ending the round with zero deadwood, for a bonus.
Undercut: When the player who did not knock ends up with equal or less deadwood, stealing the points.

Setup

Deal 10 cards to each player.
Place the rest face down as the stock and turn the top card face up beside it as the discard pile.
The non-dealer may take that first face-up card. If they pass, the dealer may take it. If both pass, the non-dealer draws from the stock and play begins.

How to Play

Turns alternate. Each turn is two steps:

Draw either the top card of the stock or the top card of the discard pile.
Discard one card face up. You may not discard the same card you just picked up from the discard pile.

Unlike plain Rummy, melds stay secret in your hand until the round ends. Card values are face cards 10, aces 1, and everything else face value.

Ending the round

Knock: at the end of any turn, if your unmatched cards total 10 points or fewer, place your discard face down and lay out your hand as melds plus deadwood.
Gin: if all 10 cards form melds, you have gin.
Once you knock (but not on gin), your opponent lays out their melds and may lay off their own deadwood onto your melds to reduce their count.
If only 2 cards remain in the stock and neither player has knocked, the round is a draw and the dealer deals again.

Scoring & Winning

Knock: score the difference between the two deadwood totals.
Gin: score 25 plus your opponent's entire deadwood. They cannot lay off against you.
Undercut: if the opponent's deadwood is equal to or lower than the knocker's, they score the difference plus a 25-point bonus.
First to 100 points wins the game, usually with a 100-point bonus for winning and 25 per hand won.

Example

You draw the 5♣ and discard the 9♦, leaving your deadwood at 8 points. You could knock now, or hold on one more turn hoping to turn your last three loose cards into gin.

Variations

Oklahoma: the value of the first upcard sets the maximum deadwood you may knock with, not always 10.
Hollywood: three games are scored at once on a running sheet.
Straight gin: knocking is not allowed at all - you must go gin to end the round.

Tips for New Players

Knocking early with 8 or 9 deadwood is often better than waiting for gin. A small score is safer than getting undercut.
Discarding a card your opponent just picked up near is risky. Track the ranks and suits they take.
High cards you cannot use should go early, while they are still cheap to throw.