Here is an overview of the TRIPE bidding system for the cardgame contract bridge. TRIPE stands for Tenaciously Resists Interference and Preempts Enemy. The T can also stand for Tenuously, since I couldn't think of a better name for the system! This is version 1.1.

The general philosophy of TRIPE is that the opening bids should be as descriptive (which makes it more robust against enemy interference) and as preemptive (three weak 2s and two types of weak 5-5 shapes can be shown) as possible. The 1♣ bid is usually made with a balanced hand without a five card suit, so responder can safely assume this to be the case unless opener takes further action to indicate otherwise (which would show an extremely strong or game forcing hand). The 1♦, 1♥ and 1♠ openings (usually) show at least a five card suit, and the 1NT opening shows at least five clubs as well, making them very resilient to competition. The bids 2♣ through 2♥ all show either a weak 2 in the next suit up, or a strong two-suited hand of a specific type. Again these are resilient to interference because any further, unprompted action from opener immediately tells responder that the strong two-suiter is held. Further details regarding how to deal with interference can be found at the bottom of the page.

A general principle when designing TRIPE was to use repeated patterns to aid recall. For instance, opener's rebid following the five responses to the 1♣ opening all follow a very similar pattern: step 1 is 19-24 balanced or an Acol strong 2; step 2 shows 11-14 balanced; step 3 shows 15-18 balanced; higher bids show a game-force of some description. Over the 2♣, 2♦ and 2♥ openings, responder assumes opener has a weak 2 and can sign-off or invite on this basis. If responder signs off, then opener bids on anyway with the strong two-suiter, and these rebids follow the same pattern in all three cases. If responder invites, then opener makes an OGUST-style rebid with the weak 2 hand or a higher rebid with the two-suiter; the meanings of the higher level rebids follow exactly the same pattern as the rebids over an initial sign-off (but exactly one level higher), which again helps with memory retention. In many cases, the system favours simplicity or repetition over accuracy. This is to make it easier to pick up and play, as well as fun – the occasional systemic loss will have to be accepted. I'm sure it could be much improved by those who are happy to learn long series of nested relays by rote!

As explained, I see the main advantages of TRIPE being its descriptive and preemptive nature, plus its prioritising of repetition and simplicity. What about the disadvantages? I'm sure there are many. Three that immediately spring to mind are:

  1. The 1♣ opening makes it very easy to miss low-level 4-4 fits in a major. This is the same disadvantage of opening 1NT in a conventional system. However, in the latter case it will only happen for a specific point range (e.g. 12-14, 15-17). In TRIPE it will happen much more commonly. Of course, this may or may not result in a bad score, since it will be hand-dependent.
  2. Occasionally, the 1♣ opening leads to playing in a 2♦ contract in a 5-1 fit.
  3. The 1NT opening (showing clubs) is both an advantage and a disadvantage. On the one hand it is very preemptive and descriptive, on the other hand it takes up a lot of room and can preempt our own auction. Experience indicates that it is better to bid optimistically to ensure that game is not missed. This, of course, means that TRIPE bidders will often get too high.

Without further ado, here is the full TRIPE system. It's a collapsible tree view, so you can click on each bid to reveal the list of responses. A greyed out bid means there are no explicitly defined continuations: any further bids are just common sense. Please note that I've gone quite deep on some of these auctions for completeness, but most of the artificial bids are only a few levels deep. Continuations after the artificial bids are supposed to be natural and logical, based on standard bidding principles. I could have left most of these out but I wanted to be as comprehensive as possible.

A strong two-suiter is strictly a hand with 16+ HCP, or 13+ HCP concentrated in two five-card (or longer) suits.

✶ artificial
♮ natural
𝄫 sign-off
♭ non-forcing
♯ forcing
? game invitational
‽ slam invitational
† game forcing
‡ slam forcing

Against interference, the general rule is that we ignore any double of opener's bid (i.e. system remains on), but that we revert to natural bidding over any other interference (i.e. system is off). Opener has already revealed a lot about their hand, so the meaning of any further bids should be clear.

Without any indication of strength from responder following a 1♣ opening, opener can adopt the following guidelines when bidding on over opposition interference. Firstly, with a game force or Acol strong 2 in a suit, opener should make this clear by jump-bidding in that suit, or bidding it at the 3-level or higher if no jump bid is available. With a game forcing no trump hand, opener should cue bid the opposition suit. With a hand of at least 15 points, opener can bid no trumps with a stop in the opponents' suit. Opener also has the option of doubling for takeout, or bidding a 4-card suit at the cheapest level. Both these bids indicate a desire to compete and suggest a non-minimum hand. Stronger hands that are short of a game force can be shown by either doubling, then bidding a suit, or else jump bidding in no trumps. Finally, any raise of responder's suit is simply competitive and does not require any extra strength.