Disclosure of Systems & Conventions

(updated January 2015)

The principle of adequate disclosure requires that competitors fully disclose all conventions and treatments requiring defensive preparation. In addition to the Simple System Disclosures (SSDs), pairs should use SSD Extras (when introduced) or Standard Messages to achieve this objective.
Although we have SSDs, it is not part of the World Bridge Federation (WBF) Regulations (under which we play unless otherwise stated) that players must look at their opponents' SSD to find out whether a call is natural or conventional. It is therefore very necessary to alert all non-natural calls.


Unless otherwise stated, we follow the WBF Regulations on alerting. The WBF Regulations are shown separately on this page. BCL interpretations and exceptions are shown in red.

This means that you …..


• Alert a 1C opening bid if you are playing a Strong Club system, or if partner could have fewer than 3 clubs, but don’t alert a 1C or 1D opening that shows at least three cards in the opened suit

• Alert transfer bids. Alert all completions.

• Alert Stayman. You must also alert a 2D response though this is not a serious offence if you are playing ordinary Stayman. (Our TD is very unlikely to adjust a score for you if your opponents don’t alert Stayman and you don’t ask, even though it is alertable).

• Alert all Game Force opening bids (eg 2C) and conventional responses (eg denial, relay, step). Also alert “2 over1” game force responses. (Again, our TD is very unlikely to adjust if a 2C opener or 2D response is not alerted and you don’t ask, even though these are alertable.)

• Alert any forcing responses to opening bids or overcalls with a special meaning, eg Ogust, splinters, cue bids, Jacoby 2NT, Inverted Minor Responses. Also, alert non forcing change of suit responses to an opening suit bid if an unpassed hand, eg Weak Jump shifts, disturbed bids if non-forcing.

• Alert Benji 2C and 2D bids and conventional responses

• Alert any two- or three-suited calls (eg Lucas/Tartan 2s, Multi 2D, Michaels, UNT, CRO, some 1NT defences).


Don’t alert doubles unless they have very unusual meanings. Very unusual doubles include (and are not limited to):

• Doubles of opponents’ opening 1NT that are not for penalties

• Doubles of RHO’s natural suit overcall of partner’s suit opening that are for penalties (because most players use negative doubles here)

• Doubles that ask for a different lead than in the suit you have doubled (eg Lightner doubles, Non-lead doubles)

Don't alert any 2-level openings if they show one natural long suit in the suit bid, whatever agreed strength, but do alert if the bid has any other meaning eg a 2 suited hand

Don't alert NT openings if they are natural and balanced, but do alert if you have an agreement that you may hold a singleton (in which case, it isn’t balanced). Do alert a 2NT opening that shows the minors

Don't alert (nowadays the software won’t let you alert) bids above 3NT eg Blackwood, rkcb, Gerber - except if a conventional bid on the first round of the auction.


Alerts are there to help and inform. They are not there so you can score bridge-lawyering points off opponents who don't alert "obvious" alertable calls like some above

The general rule is "if not sure then alert"

Then, if you are declarer or dummy, explain anything that you think opponents may not know before the opening lead. But if you are defending, don't explain (as it gives Unauthorised Information (UI)) until end of play.

WBF Regulations


1. Full disclosure is vital. Players are expected to protect themselves to a large extent. They are also expected to observe the spirit of the Laws as well as the letter.

2. The Policy has been made as simple as possible. Players are, however, expected to alert whenever there is doubt.


The following classes of calls should be alerted:

1. Conventional bids should be alerted, non-conventional bids should not.

2. Those bids which have special meanings or which are based on or lead to special understandings between the partners. (A player may not make a call or play based on a special partnership understanding unless an opposing pair may reasonably be expected to understand its meaning, or unless his side discloses the use of such call or play in accordance with the regulations of the sponsoring organization). See Law 40(b).

3. Non-forcing jump changes of suit responses to opening bids or overcalls, and non-forcing new suit responses by an unpassed hand to opening bids of one of a suit.

Do NOT alert the following:

1. All doubles except very unusual doubles – see below.

2. Any no-trump bid which suggests a balanced or semi-balanced hand, or suggests a no-trump contract.

3. Any call at the four level or higher, with the exception of conventional calls on the first round of the auction.

Nevertheless, players must respect the spirit of the Policy as well as the letter.

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