Alerting Rules Summary
The general principle is to alert calls that the opponents may not fully understand, or may reasonably misinterpret. The following summary is not intended as a complete guide - the full set of Alerting Regulations can be found on the ABF Website.
Alerting Procedure
Alerts are compulsory - you cannot ask the opponents not to alert. The requirement to alert applies even though the convention, treatment or other agreement may be listed on the system card.
All doubles, redoubles, cue bids and calls at the 4-level or higher, except conventional opening bids are self-alerting. Do not alert these calls as they are deemed to have alerted themselves.
A cue bid is defined as a bid of a suit shown by an opponent or of the denomination bid by an opponent.
Skip bids are not given any special status - generally they should be alerted if conventional and not alerted if natural.
Bidding style is not alertable. Some players bid 'up the line', some prefer to show a major ahead of a 4 or even a 5 card minor, some skip a 4 card major in making a NT rebid, etc. Be aware of these different approaches and protect yourself by asking where necessary.
There are three stages of the alert procedure, viz .
The pre-alert stage before bidding starts.
Before the round starts you should draw the opponents’ attention to any unusual agreements you have which might surprise them, or to which they may need to arrange a defence (e.g. unusual two level openings, transfer pre-empts, canapé style bidding, etc.) Pay particular attention to unusual self-alerting calls (e.g. very unusual doubles, unusual cue bids of the opponents’ suit, etc.). Highly unusual carding (e.g. leading low from doubletons) should also be pre-alerted at this stage.
Alerts during the auction.
Alert all conventional bids and passes below the 4-level. A natural bid is alertable if it is forcing or non-forcing in a way the opponents may not expect, or if its meaning is unexpectedly affected by other agreements (e.g. canapé sequences, jump responses to an opening bid or overcall that are weak, a 1H opening that denies 4+ spades, etc.). Alerts are made by audibly saying, "Alert" and, if written bidding is in use, circling the call on the bidding pad. (If bidding boxes are in use, an alert card should be placed across the relevant call.)
Delayed alerts.
At the end of the auction, the declaring side should draw attention to any unusual features, particularly any unusual self-alerting calls. Takeout/negative-type doubles and penalty doubles do not require a delayed alert, but support doubles, single suited doubles and other conventional doubles do. Defenders must not give delayed alerts. Delayed alerts should be indicated by a small plus sign (+) in one corner of the appropriate square of the bidding pad as evidence of the delayed alert. (If bidding boxes are in use, the declaring side should verbally indicate which unusual calls require a delayed alert.)