MUTOS is based upon strong clubs, ref. Precision : all (strong) hands from 16+hp onwards go via 1.

MUTOS is a FIVE-card based system. 1/ therefore promise at least a 5 card. The 1-opening promises a 5 card minor : OR OR both. All 12-15hps hands without 5 card disappear in the 1NT-opening. Yes, also the 4441-hands.

Pecularities :



All hands from 16+hp onwards or equal via a special distribution : Zarpoints 32+ zp.

The opener is the leader of the auction and takes initiatives. His partner answers his questions. The bidding space is optimally used via steps .Without overcalls and before 3NT is reached, the opener will know the distribution and strength of his partner. This is possible to due to a strict first-round answering scheme and the Relative Suit Code convention that allows the partner to indicate suits in a stepwise, abstract manner.


Counting on a 5 card minor at openers side, the partner has ALWAYS a competitive escape bid : 2/3/4 , pass/correct...
This makes the 1NT answer ( = normally 6-9hp) free for something else.
We recognize the high importance to see early the difference between a 4 or 5 card major at partners side. We can do this via 1 = 5 card, 0-9hp, and 1NT (!)= 5c , 0-9hp. The 4c major at partners hand can be shown via a MULTI-like answer : 1 , promising either a 4card OR 4 card . We extend even this multi with a possible strong hand , enough for game (12+). After a 1answer, the opener can show in his rebid whether or not he holds a 4 card major and as such , make path for a fit in a major suit if one exists.

When the opener shows a 4 card holding, after a previous 1 answer, the partner has 2 relay bids . One that denies a fit in that suit and one that acknowledges a fit in that suit. The first one (R1-8) asks to reveal 1) the minor suit, 2) a stop in the other minor, 3) his strength ( min/max). The latter (R2-4) asks to tell 1) the minor suit 2) his strength.

The 5card majors with 10+hp are brought via transfers : 2/. Those transfers are always accepted unless the transfer is routed to a singleton. The level of acceptance shows the strength of opener : minimal on a 2 -level, maximal on the 3-level. After a minimal rebid of opener, the partner can show strength via 3(alert) and ask 1) the nature of support and 2) the identity of the minor suit.
When maximal , the opener wil bid directly game when holding a 3+card support. If that 3card is not present, the opener can show

Having a 2 escape bid is also the origin for a new convention when getting overcalled with a 1-level bid or double : negative pass, promising a 4 card in the unbid major(s).

When getting overcalled (with for instance 2), the partnership MUST make a choice in what to do with the 2/ answers : competitive of 10+hp?
Both approaches can work but never together...We consciously chose for the 'constructive' approach and expect 10-11hp , RF, behind the 2/ answers.


A natural five card opening from 12 till 15hps (< 32zps). We foresee 2 strong (10+hp) relay bids :

So, other answers are weaker.

We define a gate for long weak suits : 2NT . The opener is obliged to bid 3 P/C. This opens the entire 3 level for the use of inverted Bergen Raises :

Inverted Bergen Raises, reflecting a 4 card support in the opening major :


12-15 honorpoints without a 5 card. Also a 4441-hand fits in this definition. Experience prooves that this is NOT a problem : if partner passes and has no values in the singleton suit, the opponents will often (almost) bid that suit. If partner transfers to the (major) singleton , the opener can refuse the transfer, showing his partner the 4441 holding.

Opponents who double the opening could be a problem but also here a sufficient re-action exists : 2x means a two suiter (4-5 /4-5) in x and x+1. Pass means either 9+hp, either weaker with a 2 shape-suiter ( or ). Redoible means a 5 card in unkown suit and expects oenr to bid 2, only if this RHO passes.

There are two ways to show a possible strong hand :

A partner with at least 10+ honor points will attempt for game via 2 if not holding a 5 card major. The 2 bid is NOT really Stayman although is looks like. It does asks for the major suits but when minimum (2level rebid) 2 is the answer to show both. When maximum (3 level rebid) the major suits are shown in a RSC-step wise way. We baptise this 2 complex as 'LSA - Long Suit Ask" .

Minimal This enables a medium partner to stop at this level. A stronger partner though can ask for the 2nd longer suit ( if any) via 3, the cheepest bid just beyond 2NT. The answer is from low to high : s1/2/3 : none/ / .

2 = 2x4 card major

2 = 4card

2 = 4card

2ZT = no 4 card major
3 = 4card A JNB asks for the next possible 4card, given via RSC from low to high. Applying this JNB suggests a very strong hand as the answer can be beyond 3NT.
3 = 4card
3 =2x4 card major
3 = no 4 card major
A maximal 4441 holding is told as follows :
3NT : 4441 with sn Except after 3NT, if partner continues by bidding the sn, it is a request to end in 4NT. After 3NT, 4/4/4NT = MARC convention.
4 : 4441 with sn
4 : 4441 with sn
4 : 4441 with sn