As with much of bridge bidding theory, there are some good ideas out there, but they require work on the part of both partners. I play BART over 1M 1N 2C. It’s very common these days for 2C to show 2+, with 2D promising 4+. This makes it easier to pass 2D or raise them, and has the benefit of increasing the frequency of the 2C rebid Increasing the frequency of the 2C rebid increases the availability of bart, which is usually played only over that 2C rebid One problem is that there are multiple versions of bart…I play very different versions in my two partnerships I don’t have a strong preference…I play what partner prefers. In my main partnership, and not going into detail about later auctions (but if you play this, you MUST discuss later developments in order to use it optimally) 1M 1N 2C Slightly different for 1H than for 1S, so 1S 1N 2C: 2D shows 5+ hearts. If 5, then any strength. If 6, then invitational strength…weaker hands bid 3H instead 2H puppets to 2S…responder is often passing but may be about to make a constructive bid… 2S shows 8-10 hcp and 2 spades 2N is invitational but promises 4+ clubs (allowing opener to run to clubs with a weak unbalanced hand) 3C is very constructive but denies the ability to bid 2N 3R shows 6+ and is less than invitational 3S is a 3 card limit raise with weak trump….Qxx or stronger bids 2H to puppet to 2S then raises After 2D, opener bids 2H with 2+ (usually) and otherwise makes a descriptive bid…often 2S (doesn’t promise more than 5) or 2N….extras, usually around 16-17 hcp, may have 2 hearts, 3C with 5=5 blacks, or 3H with extras and 3 hearts After 2D 2H, responder can raise hearts with 6+ and invitational values or bid 2S with 2 spades, 5 hearts and 8-10 hcp, or bid 2N, invitational with 5 hearts, etc There’s more to it than this: I have several pages of notes in both partnerships, in which the main difference is that in one we go through 2D with weak hands and bid directly with better, while in my main one, we do it in reverse. I won’t set out the 1H sequence…I can pm if asked. Most people hear about bart as a way to show hearts but it’s really much more about how responder can distinguish between weak and strong hands, within the context of the forcing 1N response.