Gamma is a trump asking bid in Responder's trump suit (unless that suit is known to be of exactly 4-card length, when a 4441-shape hand has been described, in which case the Eta Ask is used). There are effectively 3 different scales for Gamma depending on whether or not the length of Responder's suit is known or not, and, if it is not known, whether this may be a 3-card holding in a Minor suit (ie: Forcing No Trump and Opener rebids 2 or 2).

In practice, the "length known" scale is rare in this system (over Weak 2's only), but is included for completeness. Gamma is normally used with 5-card or longer suits, but in the case of Forcing No Trump sequences where Responder is using Gamma in Opener's second suit they will sometimes be only of 4-card length. In this situations Responder should be aware that Opener might open a 5-card Major and rebid a 6-card Minor, so the responses to Gamma, which are open-ended, can become very expensive.

When is a Bid Gamma?

A bid is Gamma in the following situations:

Responses to Gamma

There are effectively 4 different scales of responses to Gamma
"Length Unknown" Scale
This is the normal scale for Gamma and is used when the length of partner's suit is not known but is known to be of at least 4-card length:
  1. : No Top Honours (any length)
  2. : One Top Honour (minimum length)
  3. : 2 or 3 Top Honours (minimum length)
  4. : One Top Honour (min length +1)
  5. : Two Top Honours (min length +1)
  6. : Three Top Honours (min length +1)
  7. : One Top Honour (min length +2)
  8. ...etc etc (open-ended)
"Length Known" Scale
This scale for Gamma is used when the length of partner's suit is exactly known and is longer than 4 cards. As stated above, this scale is generally not used in this system with the exception of Gammas over Weak 2 Openings.
  1. : No Top Honours (No Repeat Gamma allowed)
  2. : One Top Honour
  3. : One Top Honour and the Jack
  4. : Two Top Honours
  5. : Two Top Honours and the Jack
  6. : Three Top Honours (No Repeat Gamma allowed)
Forcing No Trump Scale
This scale for Gamma is used in Forcing No Trump sequences when Opener has rebid what might be a 3-card Minor (eg: 1-1NT-2) and Responder is making a Gamma Ask in that Minor.
  1. : Any 3-card holding. (Suit is not agreed as trumps) Now a further Relay by Responder is asking about the 3-card suit:
    1. : No Top Honours
    2. : 1 Top Honour
    3. : 2 Top Honours
  2. : No Top Honours (any 4+-card length)
  3. : One Top Honour (4-card length)
  4. : 2 or 3 Top Honours (4-card length)
  5. : One Top Honour (5-card length)
  6. : Two Top Honours (5-card length)
  7. : Three Top Honours (5-card length)
  8. : One Top Honour (6-card length)
  9. ...etc etc (open-ended)
"Set Up Suit" Scale
This scale is only used in two specific sequences where Opener has shown a setup 6+-card suit over a Forcing No Trump: Here we have a assume that Opener's minimum holding is AKQxxx, and in the unlikely event that a Gamma Ask is required, the responses relate solely to the length of Opener's suit, ie:
  1. 6-card length
  2. 7-card length
  3. 8-card length

Repeat Gamma Asks

Unless Responder shows all 3 Top Honours, or No Top Honours when their length is exactly known, Repeat Gamma Asks are permitted to clarify Responder's exact holding in the trump suit. These are allowed below game level only, unless slam values have definitely been established, in which case they are even allowed at game level. Sometimes a Repeat Gamma at Game level may be "ambiguous". There are four scenarios, depending on the scale being used and what Responder has shown in response to the first Gamma Ask:




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OCP System Change Log
Cancelling Suit Agreement after Gamma or Eta (14-Oct-2021)
This is a clarification rather than a genuine change:
  1. After any use of Gamma or Eta, the general position is that the mere use of those Asking Bids agrees the suit as trumps. However...
  2. If the initial response shows No Top Honour in the suit and the next bid up is a bid in No Trumps, then that bid in No Trumps cancels out the suit agreement, is not Relay Beta, and is rather HoC or "to play".
  3. If the suit agreed is a Minor suit, or any time that a bid in No Trumps is made immediately over the Gamma or Eta response that is not a relay, then that bid in No Trumps is HoC or "to play" (depending on the level) unless it is obviously strong or invitational.
  4. This applies to all situations where Gamma or Eta is used, including when a 2-way transfer has been made after a 2 Opening.
Interference over 2 Openings (07-Apr-2017)
Completed documentation of interference immediately after Responder makes a 3-way Transfer, and also immediately after Opener either completes or denies a 2-way Transfer. This had never been fully documented before, so not repeated here. See the section on Interference on the Simple 2 page.
Gamma if Opener has a setup 6+-card suit (20-Mar-2017)
When the bidding has started 1-1NT-2NT(setup 6-card suit)-3(Gamma) or 1-1NT-2NT(setup 6-card suit)-3(Gamma), it makes no sense to use any normal scale for Gamma, because Opener is always showing a suit such as AKQxxx (or perhaps very rarely KQJ10xx). In these circumstances, however, we still need Gamma (1) to set the trump suit and get us into an Asking Bid sequence, and (2) to check on Opener's length.

The scale for Gamma that we now use is identical with the Repeat Gamma scale used when Opener has shown no top honour, ie: 1 step shows 6-card length, 2 steps shows 7-card length etc etc.
Responses to Two Diamond Opening (16-Dec-2016)
This is a major overhaul of the Simple System 2 Opening:
  • The 2 Response and continuations are largely unaffected, except that some hands that would originally have bid 2, now do something else.
  • The 2 Response now shows any 0-4 single-suited hand. Opener bids 2NT with a lower-range hand, but Oliver's Twist at the 3-level with an upper-range hand.
  • The Responses from 2NT through to 3 are now all 2-way transfers, showing either:
    1. 0-4 HCP with any any touching 2-suited hand or even 4333 or 5332 where the suit above their 4+-card suit is at least 3-card in length, or
    2. 14+ with any 2-suited hand, normally transferring into the cheapest or lower-ranking suit, but optionally into the high-ranking.
    Opener completes the transfer with a 4-card holding in the transfer suit and relays in the suit above with a singleton in the transfer suit. If Opener bids the transfer suit, Responder normally passes with any 0-4, but with 14+ treats the bid as Gamma. If Opener skips the transfer suit, again Responder normally passes with 0-4, but with 14+ bids their second suit as Eta (Cheapest bid in NT's normally is Gamma in the suit Opener actually bid.
  • For full details, please see the re-written 2 page.
Interference over a Positive Response to 1 (01-Oct-2009)
The use of D1P2/R1P2 and backwards Asking dates back to the original description of OCP in the late 1980's. Opener's action after interference immediately over a Positive response to 1, however, has always been somewhat different. Prior to 2009, there was a long list of what Opener should do depending on what the Positive response showed, and what the interference was and what it showed. This was difficult for everyone to learn and remember.

In 2009, following the advent of Relay Beta in 2008, that list was scrapped and replaced by four simple rules:
  1. If Responder showed a balanced hand, then over the interference, Pass was Beta and Double an Ask in the suit below the last suit bid.
  2. If Responder made a Positive showing a 5+-card suit, then over the interference, Pass was Gamma in Responder's suit and Double an Ask in the suit immediately below the last suit bid.
  3. If a cheap Gamma was available as a relay over the interference, then that was used for Gamma and Pass was an Ask in the suit two below the last suit bid.
  4. In the event of pre-emptive interference overthe positive response, then Pass was reserved at Lebensohl (forcing a Double), and Double was now Gamma or Beta, depending on whether Responder had shown a suit or not.