BART is employed after 1♠ -p - 1NT- p - 2♣ (where 1NT is forcing or semi-forcing). In BART 2♦ is artificial and asks partner to bid 2♥ unless partner has a hand that would bid over a 2♥ signoff. BART sacrifices the ability to bid 2♦ weak, but allows a partnership to distinguish, between, a weak and strong 2♠ preference, a weak hand with just hearts or a hand with hearts that also has other places to play, and it also allows responder to show 4 card club support with out going past 2NT.
The original version of BART switched the meanings of 2♦ and 2♥, but this version allows you to show more hand types and is just as easy if not easier to remember.
- 2♦ BART - either to play 2♥, or various other hands.
- 2♥ 5 hearts and another place to play (such as a doubleton spade, 4 clubs, 5 diamonds, 1543, etc.)
- 2♠ Either very weak with 3+ spades or up to 8 HCP with doubleton spade.
- 2NT 10+ - 12 (with 10 HCP and 2 spades, you can also bid 2♦; 10 HCP and a stiff spade may need to bid 2NT). Should deny 4♣s.
- 3♣ Courtesy raise with 5+♣s.
- 3♦ FJS for clubs. NOT FORCING but highly encouraging. 4♣ not forcing. Other non-game bids forcing, including 4♦.
- 3♥ FJS for clubs, as above.
- 3♠ 3-card limit raise.
1♠ -1NT-2♣ -2♦
- 2♥ All minimum hands. Opener only breaks with a hand good enough to bid over a natural ♥ signoff.
- 2♠ Artificial, shows minimum strength up to about bad 16 but would raise a natural 2♥ signoff, eg. Axxxx QJx x AKxx.
- 2N Extras, 5224 or 5134.
- 3♣ Extras, 5-5.
- 3♦ Extras, 5044.
- 3♥ Extras, 5314.
- 3♠ Extras, 6-4.
1♠ -1NT-2♣ -2♥
- 2♠ Usually stiff or void in hearts though can be small doubleton. Nonforcing ask for the other place to play.
- 3♥ Invitational raise with 3 card support likely (but maybe KQ xx in red suits) .
- Others Same as over 2♦.
1♠ -1NT-2♣ -2♦ -2♥
- Pass You play this, even with short hearts.
- 2♠ Normal preference but on the good end, about good 8 to bad 10.
- 2N 10 to bad 12, natural invite but promises exactly 4 clubs. If opener pulls to 3♣ that is to play, other bids are forcing.
- 3♣ Invitational raise, 5+♣ s.
- 3♦ Weak with diamonds, to play here.
- 3♥ 2-6 in the majors, invitational (1♠ - 3♥ is ostensibly 1-6 in the majors if you play downward invitational jump shifts).
- 3♠ Balanced limit raise, will pass if you bid 3NT.
Now, it may seem like quite a lot to digest all at once. The easy way to remember the difference between bidding something directly and going through 2♦ is that going through always shows something extra. For example after 1N-2♣-2♦-2♥: 2♠ is stronger than bidding directly, 2N shows 4 clubs, and 3♣ also has more values then bidding directly.
If you do choose to play BART, your partnership should bid 2♣ on a doubleton instead of a 3 Card ♦ suit. This allows you to take fuller advantage of your gadget and responder also knows that opener’s 2♦ bid promises 4.