Background
A problem arises when a player opens and the next player does not know the meaning of the bid. This is information to which they are entitled.
If they have a hand with few values, they will pass regardless of the meaning of the bid. However, suppose they have some values and would bid if the opening bid was a normal opening bid, but not if it was a strong hand. Also, suppose they have a hand with which they would compete over a weak NT, but not over a strong NT. If the player enquires about the meaning of the bid, or the NT range, and then passes, then they have conveyed information to their partner. They have said, "I have more than a few values and would have bid if the 1C was an Acol 1C but now that I know it promises 16+ HCP, I will pass" or "I have enough values to compete over a weak NT but now that I know it is strong, I will pass". Their partner, with a marginal hand, may now be tempted to bid, which they would not have done if the pass had been made without the enquiry.
How then, can this issue be avoided?
Announcing
NZ Bridge has decided to introduce Announcing to ensure that the nature of a 1C or 1NT opening bid is immediately clear. The opponents will have no need to make an enquiry or closely inspect the System card when they have a "will I or won’t I bid" hand and then follow with a pass, except if the 1C is announced as "unusual" when they may need more information before deciding on their call.
The partner of a Player who makes a 1C or natural 1NT opening bid shall promptly alert the opponents by announcing their systemic agreement using the following descriptions.
For 1C opening bids in:
Natural (Green) systems
The appropriate length of the club should be announced, i.e. ("2 plus", "3 plus","4 plus" etc.).
Strong Club (Blue Systems)
The word "Strong" together with the minimum HCP holding (e.g. 16+) should be announced.
System options other than those above (e.g. a Polish 1C)
The word "Unusual" should be used.
For a natural 1NT opening bid:
"12 to 14" (or the appropriate range).
Announcing is now required when a 1C or 1NT Opening Bid is made. This regulation has been introduced to make the process of correctly informing your opponents of the meaning of these bids and is quick and simple. Failure to announce will not result in an automatic procedural penalty but a reminder that the Regulations do now require Announcing.