These 4 articles appear(ed) in the ACBL Bulletin (Dec 94?) -MB These articles were written by -- Karen Walker, Champaign IL She has an excellent bridge site at http://www.prairienet.org/bridge
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                      Your 2C Bidding Structure
                   Part 1 -- IS this a 2C opening?
 
   Back in our game's early years, the experts of the day emphasized
"sound values" in bidding.  Opening notrumps were 16-18 points, jump
shifts were 19+, and preempts always followed the rule of two and three.
Every bid seemed to promise "two bull elephants backed up in the garage"
(as one of our local rubber bridge players used to say).
   Today's players like to bid higher and more often than Culbertson,
Goren and the other bridge pioneers.  As a result, modern bidding has
embraced lower minimums for many standard bids and conventions.
   One of the bids that has undergone this reverse inflation is the
strong two-bid.  It doesn't "cost" nearly as much to make one today as it
did forty (or even twenty) years ago, when it virtually guaranteed game.
Back then, Goren recommended a minimum of 25 high-card points with a good
5-card major, 23 points with a 6-carder, and 21 points with a 7-carder.
In a minor suit, two points more were required.
   Today, most players have switched to a strong-and-artificial 2C, and
they open it with somewhat less than Goren recommended.  Some even
stretch the limits to include any hand with 8 to 9 playing tricks.
   I still remember a long-ago club game where one player opened a strong
2C with  S-5  H-AQJ10987542  D-6  C-8.  In the mayhem that ensued (his
opponents had missed a slam), he defended his bid with some creative
arithmetic:  adding in distribution and 2 points for each card after the
fourth in his suit, he counted 25 playing points.  He was also quick to
quote all the old rules -- "I have 9 playing tricks, I don't have two
quick losers in any suit, I want to force to game ..."
   If you use a playing-tricks-only definition like this one, your 2C
openers may encompass weak, distributional freaks like the hand above.
However, it's a marked deviation from what most players consider a
"standard" 2C opener -- and what experts recommend.
 
Put your hand to the test
----------------------------
   So what type of hand should you have for a strong 2C?
   With a balanced hand, your decision is easy because you can rely on
high-card points.  If your range for an opening 2NT is 20-22, you need 23
points to open 2C and rebid 2NT.
   Unbalanced hands involve more difficult decisions because you have to
evaluate your hand in terms of both trick-taking power and defensive
strength.  In making decisions about whether or not to open 2C with a
distributional hand, many good players "test" their hand with some
combination of the guidelines below:
 
   1 - Playing tricks -- at least 8 1/2 to 9 tricks if your long suit is
       a major; 9 1/2 to 10 tricks if it's a minor.
   2 - Defensive strength -- a minimum of three (preferably four) quick
       tricks.
   3 - Loser count -- your hand's quick tricks should outnumber its losers.
   4 - The "two-queens" test -- Do you want to be in game if partner has
       two queens and nothing else?
   5 - Possible rebid problems -- How difficult will this hand be to
       describe if you open it with a one-bid instead of 2C?
 
   Although high-card points aren't the main factor in evaluating an
unbalanced hand, it is important to remember that strong is still the
operative word in the convention's name.  A strong 2C should not be used
to describe a preempt-type hand.  In practice, your hand will seldom meet
many of the guidelines unless it has at least 16-18 honor points.
 
The Quick Tricks vs. Losers Rule
--------------------------------
   Your hand doesn't necessarily have to pass all five of the tests to
make a 2C opening a good choice.  You'll always have borderline decisions
where you'll have to use your judgment.  But if you're looking for a
"tie-breaker" to help you choose an opening bid for a strong, unbalanced
hand, one of the most useful guidelines is the loser count (#3 above).
   Using this evaluation method, you open 2C only with hands that contain
more quick tricks than losers.  To count your quick tricks, use the
standard formula (each ace or KQ combination is 1 quick trick; an AK is
2; an unsupported king is 1/2; and an AQ is 1 1/2).
   Note that quick tricks are not the same as playing tricks.  A hand
with a solid 9-card suit and no other honors will have nine playing
tricks, but only two quick tricks (the AK) and four outside losers.
   To determine your hand's total losers, count one for each missing ace,
king or queen in each suit of 3 cards or more (up to a maximum of three
in any suit).  In shorter suits, count only missing aces (for singletons)
or aces and kings (for doubletons).  Voids, singleton aces, AK doubletons
and suits headed by AKQ have no losers.  Ax and Kx are each one loser;
any lower doubleton (including Qx) counts as two.
   There are a few distinctions you'll want to make with this formula.
Technically, suits of Axx, Kxx and Qxx (or longer) each have two losers,
but these obviously aren't comparable holdings.  For this reason, you
should count a queen-high suit as three losers unless it also contains
the jack or it's a long suit that's likely to be trumps.
   Another exception is a holding of AJ10(x).  Even though you're missing
the king and queen, this suit is usually counted as only one loser
because of the 75% chance of a successful double finesse (this assumes,
of course, that you'll be able to lead the suit from partner's hand).
 
Try your evaluation skills
------------------------------
What's your opening bid with the following hands?

S-AK5   H-6   D-KQ987654   C-8
   Open 1D.  You could count this as 9 playing tricks (7 diamonds and 2
spades), but you should have at least 9 1/2 when your long suit is a
minor.  And even 9 tricks is optimistic -- if partner doesn't have a fit,
you could easily have 2 (even 3) diamond losers.  Since you have only 3
quick tricks and 4 losers, it's better to open with a 1-bid and hope to
describe your playing strength later in the auction.
 
S-AKQ10975   H-Void   D-AQJ10   C-52
   Open 2C.  You have dead-minimum honor strength, but this hand
qualifies on all other counts -- 10 playing tricks, 3 1/2 quick tricks
vs. only 3 losers, and you expect to make 4S opposite a 4-point hand (in
this case, a Yarborough will be sufficient).  The losing doubleton is a
liability, but that alone shouldn't talk you out of opening 2C if the
rest of the hand is "right".
 
S-AKJ   H-K   D-AQ6   C-KJ8643
   Open 1C (some would even try 2NT).  Although you have plenty of points
and defensive tricks for a strong opening, how high do you really want to
be if partner can't scrape up a response to 1C?  Your suit is so weak
that you can't count playing tricks, and you have more losers (5) than
quick tricks (4).  It's true that if partner holds the "right" two queens
(hearts and clubs), you might make 3NT, but it's seldom wise to base your
decision on the chance that partner has specific cards for you.
 
S-A   H-A105   D-AK98764   C-A3
   Open 2C.  Many would choose a 1D opening, mainly because your suit is
a minor and the hand counts to only 9 playing tricks (6 diamonds and 3
aces).  However, you have more quick tricks than losers, and holding all
four aces is a big plus.  The deciding factor here is your possible rebid
problems.  If you start with 1D and partner responds 1S, you could risk
the minor distortion of a 2H reverse.  But what if partner instead
responds 1H?  The only 100% forcing bids you'll have available (4NT
notwithstanding) are jump shifts to 2S or 3C, both of which are major
distortions of your distribution.
 
--------------------------------------------------------------------
 
                      Your 2C Bidding Structure
                   Part 2 -- Special Problem Hands
 
   The 1992 Fall NABCs in Orlando got off to a rousing start when this
hand was dealt in the first session of the Open Pairs:
   S-Void   H-6   D-AKQJ98754   C-832

   In first seat, with both sides vulnerable, what's your call?
   The recommended opening with this type of hand is 5D, or perhaps a
gambling 3NT for those who play that convention.  Several creative souls,
however, came up with more imaginative calls, including a strong 2C.
 
Is this a psyche?
--------------------
   The result at many of these tables was a director call when the
opponents questioned the legality of the 2C opening (this hand generated
five committees after the session, all at tables where the auction began
with 2C).  ACBL laws forbid psyching an opening of a strong, artificial
bid -- including a strong 2C and a Precision 1C -- so the question before
the committees was:  Is this a psychic 2C opening?
   The answer depends in part on the bidder's intent.  If a committee
believes the opener chose 2C to intentionally deceive his opponents, they
would probably rule it an illegal psyche and adjust the score.  But if
opener could convince the committee that he honestly evaluated this hand
as a legitimate strong 2-bid, the score might stand.  In practice, a
committee would probably give a novice the benefit of the doubt, but
would expect an experienced player to know better.
 
Problem #1:  Preempt-type hands
---------------------------------
   If you and your partner consider any 9-trick hand to be worth a 2C
opening, then this hand might qualify as "legal".  Whether or not it's a
wise choice is another issue.  This hand type -- lots of playing tricks,
but little defense -- is one of several that create special problems when
opened with a strong two-bid.
   Opening 2C with a hand that most players would open with a 1-bid (or
even a preempt) runs several risks.  The more immediate one is deceiving
partner.  On the hand above, partner will average about 10 high-card
points, and if he has a few quick tricks, you won't be able to stop him
below slam.  And if your next 2C opener is a 25-pointer, you'll have a
hard time convincing partner that his scattering of kings and queens will
make a slam this time.
   If your 2C opening doesn't promise some minimum defensive strength,
you'll also have some awkward problems when the opponents compete.
Responder won't be able to take strong action until opener clarifies his
hand type, and neither partner will be able to make a forcing pass or a
penalty double with any certainty.
   A third, and perhaps more serious, problem is that your non-standard
opening may illegally mislead your opponents.  So even if you get a good
result, it may be overturned or you may incur a penalty for improper
system announcement.  To be sure your opponents are informed about your
style, you should special-alert, or even pre-alert, this type of 2C
opening (although there's no guarantee that this will appease all
committees).
 
Problem #2:  Two-suited hands
---------------------------------
   Two-suited hands, especially those with both minors, are some of the
most difficult to bid with the 2C convention (and one of the reasons
forcing-club systems were developed).  Because 2C uses up so much bidding
space, expert players will stand on their heads to avoid opening 2C with
a minor two-suiter.
   Consider a hand like  S-Q  H-AQ  D-AKJ53  C-KQJ74.  Your first
instinct may be to open 2C, since you have 22 points and your quick
tricks (4 1/2) do outnumber your losers (4).  An optimist might even
count this as 9 1/2 tricks, but the deciding factor here is your rebid
problems.  To show both your suits after a 2C opener, you'll have to go
to the 4-level, which may be too high.  The best way to safely and
accurately describe this hand is to open 1D, then jump-shift into clubs.
   Even 5-4 and 6-4 minor-suited hands can cause problems.  If you open
2C with S-AQ  H-A  D-AJ109  C-AQ10873 and follow with 3C, what do you do
over partner's 3H, 3S or 3NT rebid?  You could be missing an excellent
diamond fit, but you don't have room to show your second suit or to get a
good idea of partner's strength.  Better to open this hand 1C, pray for a
response, then reverse into diamonds.
   Your strategy should be different, however, when you have a major two-
suiter.  Any of the hands above would be a good 2C opener if even one of
the 5+-card suits were a major.  Since your first rebid with these hands
will usually be at the 2-level, you should have room to show both your
suits after a 2C opening.
 
Problem #3:  Minor one-suiters
--------------------------------
   You'll also want to make distinctions between majors and minors when
you hold a strong one-suiter.  For example,  S-Void  H-KQJ10865  D-AK82
C-KQ, has 4 quick tricks, only 3 losers, and counts to 9 playing tricks --
all adequate for a 2C opening with a major.
   Switch the diamonds and hearts, though (to  S-Void  H-AK82  D-KQJ10865
C-KQ), and you'll fare better with a 1D opening.  One reason is that when
you open 2C and show a minor suit, partner will count on you to have at
least 9 1/2 tricks.  Another important consideration is that a 2C opener
makes it very difficult, and sometimes impossible, to find a 4-4 major-
suit fit, which is a real danger on this hand.  If partner has 4 hearts,
a 1D opening may be the only way you'll get him to bid the suit.
 
Problem #4:  Three-suited hands
---------------------------------
   The real bane of the 2C bidder's existence is the strong 4-4-4-1
pattern.  Players solve this problem in a number of ways, one of which is
to open 2NT.  This works best when your singleton is an honor and it's in
a minor suit.  With a hand like  S-KQ93  H-AQJ4  D-AQ105  C-K, 2NT is
fairly safe -- partner isn't likely to be bidding a club game, and your
singleton king does offer a feeble stopper for notrump.  Add a queen to
this hand, and you would open 2C and rebid 2NT.
   However, change the hand to S-3  H-AK109  D-AQJ4  C-AK75, and an
opening 2NT is more of a distortion.  Since your singleton is a major,
there's too great a chance that partner will have 6-card length and
insist on game (or slam) there.  Also, with all your honors outside the
singleton, your hand becomes more suitable for a trump contract.  Opening
2NT with this type of playing strength could cause you to miss a good slam.
   The most common way to deal with three-suited hands of up to 22 points
is to start with a 1-bid.  With the hand above, if partner can't respond
to your 1C or 1D opening, you probably haven't missed anything.  Even if
you have, you may still find it; the opponents, who rate to hold a fair
number of spades, may overcall or balance.
   Your real dilemma comes when you hold far too much strength to risk a
1-bid.  With  S-3  H-AKJ8  D-AK86  C-AKQ4, most players open 2C, then
rebid 2H (or maybe 2NT, if the singleton is a minor).  These auctions
often require good guessing and skill in playing 4-3 fits, but
thankfully, we see these 4-4-4-1 powerhouses only rarely.
   There are some handy conventions to make this type of hand easier to
bid.  One is Roman 2D, which shows a 4-4-4-1 with 17-24 points; opener's
rebids then identify his singleton.  Another interesting approach is to
play a jump rebid by the 2C opener shows this pattern with a singleton in
the next higher suit (with the above hand, the auction 2C-2D-3H would
show the singleton spade).
 
---------------------------------------------------------------------
 
                      Your 2C Bidding Structure
              Part 3 -- Choosing Your Responses to 2C
 
   Think about the last time you filled out a convention card with a new
partner. You might have gotten into long, involved conversations about
once-in-a-lifetime conventions, but when you came to the part of the card
for 2C opening bids, the discussion may have been over in two seconds.
Typically, one person will say "2D-semiauto" (or some other shortened
version of an agreement) and you're done with it.
   Even serious partnerships often devote little time to this aspect of
their systems.  But since 2C openers seem to come up about once a
session, it pays to know your options and to have some clear agreements
about these auctions with your partner.
   One important area for discussion is responder's conventional
responses and rebids.  The once-common 2D negative response (which showed
0-7 points) is used by few players today.  Modern bidding has given us
lots of new choices, each with advantages and disadvantages.
   When designing your system, it's often helpful to find out which
conventions and treatments are popular among good players.  Some
interesting answers came from a survey of players who read the Usenet
newsgroup rec.games.bridge on the Internet computer network.  This group
isn't representative of bridge players as a whole (their average age is
37), but most are fairly experienced players who have studied bidding
theory.  Those who answered the survey ranged from intermediate-level
players to world champions.
   When asked what general structure they used for responses to a strong
2C in their favorite partnership, they offered the following answers
(with the percentage of "votes" for each):
   36%      2D semi-positive, 2H immediate double negative
   25%      Control-showing step responses
   21%      2D waiting, cheaper minor second negative
   10%      2D negative, 2H balanced positive
    4%      Point-count step responses
    4%      Other artificial systems

Here's a quick look at the three most popular responding structures:
 
2D waiting (or "semi-automatic")
----------------------------------
   With this widely used approach, responder almost always bids 2D to
give the 2C opener maximum room to describe his hand.  Exceptions are
rare; responder bids his own suit only when it's very strong and he has
otherwise positive values.  Most partnerships also include a way for
responder to show an ultra-weak, "second-negative" hand later -- usually
by bidding the cheaper minor (some also use cheapest suit or 2NT).
   The advantages of 2D waiting are that it's simple and it saves bidding
space.  The drawback is that responder has fewer opportunities to
describe his strength and suit length, and may find it difficult to catch
up later in the auction.
 
Control-showing responses
-----------------------------------
   This approach is popular because it allows responder to show his most
important cards (aces and kings) immediately, all in one bid.  Counting
each king as one control and each ace as two, responder makes one of the
following step responses:
      2D = 0 or 1 control
      2H = 2 controls
      2S = 1 ace and 1 king (3 controls)
      2NT = 3 kings (3 controls)
      3C = 4 controls
   There are many variations, including one that incorporates point-count
into the first two steps -- both 2D and 2H show 0 or 1 control, but 2D
limits the hand to 0-4 points and 2H promises 5+ (or some players use 0-5
and 6+ point ranges).  2S becomes the 2-control response and the other
steps are modified accordingly.
   The disadvantages of control responses are that responder loses the
ability to make a natural call at his first turn and may use up extra
bidding space, which can make the later auction somewhat tricky.  But
since the higher steps show slam-oriented responding hands, most
partnerships don't worry too much about losing an early level of bidding.
   A few players define the steps by just point-count, but this has
little value because it makes no distinction between jacks and aces.  The
2C opener seldom has any need for knowing his partner's total points;
information on aces and kings is much more helpful.
 
2D semi-positive; 2H double negative
--------------------------------------
   This is similar to 2D waiting, with the exception that responder uses
an immediate 2H response to show a "double-negative" hand (fewer than 2
queens).  A response of 2D, then, is semi-positive, promising at least
two queens or a king.
   This offers several advantages.  Responder's 2H gives opener immediate
information about game prospects and makes it easier for you to stop in a
partscore when it's right.  Since the 2D response shows forcing-to-game
values, both partners can keep the auction low.  Also, there's no need
for a second-negative response later, so all of responder's rebids are
natural.
   Since 2H isn't available as a natural call, 2NT is used to show a
positive response with hearts (5+ cards to 2 of the top 3 honors).  A
better alternative to this is "reverse transfers", where 2S shows a heart
positive, and 2NT shows a spade positive.  This makes the strong hand
declarer if responder's suit becomes trumps.
 
Defining your other responses
-----------------------------------
   If you've decided to use control-showing responses, responder has few
other choices for his first bid.  Those who have adopted other systems
need to discuss the meanings of all the other possible bids responder
might make.
   For those who play 2D as waiting, negative or semi-positive, here are
the standard meanings (and some popular variations) for responder's other
bids:
   Suit response (2H, 2S, 3C, 3D):  Most partnerships require responder
to have a near-perfect hand for this bid:  at least 5 cards, two of the
top three honors, and otherwise positive values.  AQxxx and out isn't
enough, especially if it's a minor.
   Jump in a suit (3H, 3S, 4C, 4D):  Many pairs haven't discussed
responder's jump, but some play it as a 6-card or longer suit headed by
AKQ.  A more useful agreement is to define it as a long, strong suit
missing the ace or king, with no outside controls (something like a good
weak two-bid).
   2NT:  This usually shows a balanced 8-10 or 9-11 points (or, for those
who you play 2D semi-positive and reverse transfers, a good spade suit).
In practice, it's rarely used as a natural bid because it eats up so much
space.  Several of the Usenet players said the only time they would
respond a natural 2NT would be with a hand with good tenaces, soft values
and few controls.
   3NT:  Although the standard definition is a balanced 11-12, many of
those surveyed said they would never respond 3NT.  Instead, some use it
to show an unspecified long, solid suit.
 
   Note that few players use the old "game-in-hand" requirement anymore,
so an opening 2C isn't 100% forcing to game.  You should, however, agree
that unless the 2C opener rebids 2NT, the auction is forced to at least 3
of a major.
 
----------------------------------------------------------------------
 
                     Your 2C Bidding Structure
                 Part 4 -- Defining Opener's Rebids
 
   You open 2C (strong and artificial) and partner responds 2D (waiting
or semi-positive).  What do you rebid with each of the following hands?
   1)  S-AKJ73   H-8   D-AKQ   C-AQ73
   2)  S-AQ10875   H-AQ5   D-A   C-AQJ
   3)  S-AQJ10976   H-6   D-AK   C-AK4
   4)  S-AKQ109832   H-Void   D-AQ5   C-A8
   5)  S-AKQJ954   H-2   D-AQJ10   C-7
 
   The standard way to start the description all five hands is to open
2C, then rebid 2S.  But with such wide differences in trump quality,
playing tricks and defensive strength among these hands, a 2S rebid
doesn't begin to give partner a good picture.  You'll usually need at
least one or two more bids to clarify which hand type you hold.
   The problem comes if you and your partner haven't assigned clear
meanings to the 2C opener's later rebids.  With Hands #2 through #5, for
example, you'll have enough room to rebid spades two or three times.  But
since these are really four different hand types, do you have four
different ways to show them?
   To solve this problem, many players have added a few simple agreements
that allow the 2C opener to more accurately describe hands like these
with his first and second rebids.  They take advantage of jumps to the
three and four levels to distinguish between solid and non-solid suits
and maximum and minimum playing strength.
 
Non-jump suit bid  (2C-2D-2H/2S/3C/3D)
---------------------------------------
   This starts the description of a "standard" 2C opener (Hand #1 above).
If opener's first rebid is a major, it shows either a 5-card suit or a
longer, non-solid suit.  If it's a minor, it strongly implies a 6-card or
longer suit (which may or may not be solid).
   Note that even though opener needs only a 5-card suit for this
auction, it tends to imply a one-suited or distributional hand.  For more
balanced hands, even those with a 5-card major, you may want to choose a
notrump rebid instead.  With a hand like  S-AJ1052  H-AQJ  D-AQ  C-KQ10,
opening 2C and rebidding 2S wouldn't be incorrect.  Many players,
however, would rebid 2NT to emphasize the balanced strength, take
advantage of the good tenaces, and limit their point count.
   To show extra length (Hand #2), opener rebids his suit at his next
turn.  This auction -- 2C-2D / 2S-3C / 3S -- shows a 6-card or longer
suit, but does not insist that it be trumps.  The final contract is still
open to negotiation and may be in notrump or partner's suit.
   For hands with more powerful (but not solid) suits and playing
strength (Hand #3), opener starts with the low-level rebid, then jumps to
game at his third turn.  This auction -- 2C-2D / 2S-3D / 4S -- sets
trumps, but tells partner your suit has a loser.  Any further bid by
responder (even in a suit he's shown earlier in the auction) is a cuebid
for slam in opener's suit.
 
Jump to 3 of a major (2C-2D-3H/3S)
---------------------------------------
   One good agreement for opener's jump is to use it for a powerhouse
with long, solid trumps and good controls (Hand #4).  It sets trumps and
promises a suit that should play for no losers opposite a singleton -- at
least AKQJxx or AKQxxxx (or AKJxxxxx if you have the courage).  This
agreement can also extend to minors, but because a jump to 4C or 4D uses
up so much bidding room (and takes you past 3NT), you should have an
exceptional hand to use it.
   After opener's jump, responder cuebids his cheapest ace or king.
Without one, he raises to 4 of opener's suit with a potential ruffing
value (at least a doubleton trump and an outside doubleton).  With no
controls and no ruffing value, responder rebids 3NT.  This will never be
the final contract (opener will always go back to his suit), but it warns
partner that your hand isn't suitable for any higher contracts.
   You can see how well this works with Hand #4 above.  After 2C-2D-3S,
if responder answers with 3NT, 4H or 4S, you'll know he has neither of
the kings you need and you can stop safely in game.  If he instead bids
4D (showing the diamond king but not the club king), you'll bid 6S.  And
if he bids 4C over your jump, you can look for the grand slam -- you'll
follow with a 4H cuebid and if partner can now bid 5D to show a second
king, you can bid your almost-laydown 7S.
 
Other uses for opener's jump  (2C-2D-3H/3S/4C/4D)
--------------------------------------------------
   Another interesting treatment is to use opener's jump to show a 4-4-4-
1 hand.  To identify his singleton, opener jumps into the suit directly
below it -- 2C-2D-3S shows a singleton club, 2C-2D-4D shows a singleton
heart.
   Other players are successful in using jumps to pinpoint two-suited
hands.  The method you and your partner choose depends on your personal
preference.  The key is to decide on some useful meaning for opener's
jump and not leave it as an idle bid.
 
Jump to game in a major  (2C-2D-4H/4S)
---------------------------------------
   Opener's immediate jump to game shows a minimum with 9-10 playing
tricks and long, solid trumps.  It tells partner your 2C opening was
based more on playing strength than high-card points and warns him
against bidding on unless he has excellent controls.
   As with the jump to 3 of the major, there's no looking for new trump
suits after this auction.  Any further bid by responder is a cuebid for
slam in opener's suit.  Responder should pass with just kings and queens,
but bid on with a hand that could potentially contribute two tricks.
After 2C-2D-4S, you should pass with  S-763  H-KJ4  D-K9  C-QJ1093.
However, a hand like  S-3  H-1086543  D-K9  C-A1053 is worth a 5C cuebid.
 
Handling interference
---------------------------
   With more and more opponents willing to overcall a 2C opening, it's
also important to discuss how you'll handle competition.  After an
opponent makes a direct overcall of your opening 2C, a useful set of
agreements for responder's bids is:
   New suit = A strong suit (two of the top three honors, usually with 6+
              cards).
   Cuebid = Positive response, 4-4-4-1 distribution, singleton in the
            overcalled suit.
   Pass = Any other semi-positive hand (two queens or better).
   Double = Immediate double-negative (less than two queens).
 
   Most frequently, responder will pass the overcall and let opener
describe his hand.  After the auction:
 
    You    LHO    Partner    RHO
    2C     2H      Pass      Pass
 
the meanings of opener's rebids can be:
 
New suit  (2S, 3C, 3D) = One-suited hand.  Jumps (to 3S and 4S) can
   carry the same meanings as those described above.
2NT = Two-suit takeout.  Responder bids the cheapest suit he's willing
   to play in; if opener corrects, it shows the other two suits.
Cuebid  (3H) = Three-suit takeout (4-4-4-1, singleton in the opponent's
   suit).
Double = a strong notrump hand.  This shows balanced distribution, but
   doesn't have to promise a stopper in the overcalled suit.  Responder can
   pass for penalties or bid on with standard notrump sequences (Stayman and
   transfers).
 
If the overcall instead comes on opener's right, as in:
 
   You    LHO     Partner    RHO
    2C    Pass     2D        2S
 
you can use the same agreements as above for opener's new suit, cuebid
and 2NT bids.  A direct double, however, should be penalty, since opener
can make a forcing pass to show a fairly balanced hand.