There are five negative and two positive contracts in Barbu and all are trick-taking games with the exception of Domino.
For trick-taking contracts, declarer leads a card to the opening trick and play passes clockwise with each player following suit if able, or otherwise playing a card in a different suit.
All contracts are played at no trump, with the exception of Trumps.
The total scores for all seven contracts taken together add up to zero, although variations exist where this is not the case (see variations below).
The seven contracts are:
No Tricks (also known as misere or nullo).
Each trick taken scores −2 points for a total of −26.

No Hearts.
The Ace of Hearts scores −6 and each of the other hearts score −2 for a total of −30.
Hearts may never be led unless there are no cards of other suits available to lead.
All hearts are kept face up after capture so that everybody can see who has taken which.

No Queens.
Each Queen scores −6 for a total of −24 and queens are left face up after capture.
The hand ends once all four queens have been taken.

No King of Hearts (Barbu).
K♥ scores −20, and hearts may not be led as in the No Hearts contract above.
Play ends once the King has been taken.

No Last Two.
The second-to-last trick scores −10 and the last trick scores −20 for −30 points.

Trumps.
Declarer chooses trumps and leads to the first trick.
If a trump is led, each player must, if able, play a higher trump than those played before.
Otherwise players follow suit, or discard if they are void in trumps.
If a plain suit is led, players follow suit if possible.
If they cannot and no trump has been played, they must play a trump card if possible or otherwise play a card of one of the other suits.
If a non-trump has been led and trumped, a player must, if possible, play a higher trump than those previously played.
Otherwise the player may slough off any card.
Each trick scores +5 points for +65 total.

Domino.
 Declarer chooses a starting rank (which he need not have) and announces "Domino from the [rank]!".
Each player in turn must play any card of the chosen rank or cards one higher or lower in rank than those on the table.
Failing that, a player must pass.
The aim is to be first to shed all of one's cards.
The layout of the Domino is thus built from a column of the four starting cards that sequence outward to one or both sides.
Play continues until all cards have been laid out onto the table.
First to go out scores +45, second scores +20, third +5 and last −5, for +65 total.
There are five negative and two positive contracts in Barbu and all are trick-taking games with the exception of Domino. For trick-taking contracts, declarer leads a card to the opening trick and play passes clockwise with each player following suit if able, or otherwise playing a card in a different suit. All contracts are played at no trump, with the exception of Trumps. The total scores for all seven contracts taken together add up to zero, although variations exist where this is not the case (see variations below). The seven contracts are:
No Tricks (also known as misere or nullo). Each trick taken scores −2 points for a total of −26.
No Hearts. The Ace of Hearts scores −6 and each of the other hearts score −2 for a total of −30. Hearts may never be led unless there are no cards of other suits available to lead. All hearts are kept face up after capture so that everybody can see who has taken which.
No Queens. Each Queen scores −6 for a total of −24 and queens are left face up after capture. The hand ends once all four queens have been taken.
No King of Hearts (Barbu). K♥ scores −20, and hearts may not be led as in the No Hearts contract above. Play ends once the King has been taken.
No Last Two. The second-to-last trick scores −10 and the last trick scores −20 for −30 points.
Trumps. Declarer chooses trumps and leads to the first trick. If a trump is led, each player must, if able, play a higher trump than those played before. Otherwise players follow suit, or discard if they are void in trumps. If a plain suit is led, players follow suit if possible. If they cannot and no trump has been played, they must play a trump card if possible or otherwise play a card of one of the other suits. If a non-trump has been led and trumped, a player must, if possible, play a higher trump than those previously played. Otherwise the player may slough off any card. Each trick scores +5 points for +65 total.
Domino.  Declarer chooses a starting rank (which he need not have) and announces "Domino from the [rank]!". Each player in turn must play any card of the chosen rank or cards one higher or lower in rank than those on the table. Failing that, a player must pass. The aim is to be first to shed all of one's cards. The layout of the Domino is thus built from a column of the four starting cards that sequence outward to one or both sides. Play continues until all cards have been laid out onto the table. First to go out scores +45, second scores +20, third +5 and last −5, for +65 total.
Barbu (card game)