Source: www.qldbridge.com 
Let’s face it. Misunderstandings will almost inevitably occur in any partnership, but there are some that come up more often than others. Knowing (and discussing) through these situations should strengthen a partnership, particularly if it’s a partner you play on a non-regular basis. Here are some situations where misunderstandings occur on a frequent basis, so it might be a good idea to discuss these with your partner!
Take a look at this auction: 
3=6-9pts with 4+ (Bergen Raise)
What does partner’s (North’s) double mean? Does it show something like 5 AQ85 KQ72 A943 where we might want to think about bidding 4 now, or does it show something like 75 83 Q983 AKJ74 where it’s lead directing? What if West had bid 3 (10-12 points with 4+), and partner doubles, would that be different or the same? It doesn’t really matter which you agree on (takeout of the major, or lead directing), but as long as you are on the same page!
Here’s an auction that causes frequent disasters:
Sitting as South, you open with a pre-emptive 4 and partner bids 4. Now what is 4? Is it a control-asking bid where North has something like 754 KQ AKQ96 AK8 and would like South to bid slam with a first or second round control in spades (similar to 4 -Pass-5 or 4-Pass-5 where it’s best to play those 5-minor bids as control-asking), or is it a ‘to play’ bid where it shows something like AKQ10875 – KQ3 A32 and thinks 4 is a better game contract than 4?
How about an auction that may have a confusing 4NT bid:
Is 4NT a Blackwood (or Roman Key Card Blackwood) asking in the last bid suit (hearts), or is it simply a quantitative bid asking South to pass with a minimum or bid slam with a maximum (similar to 1NT-4NT where 4NT is quantitative)? This auction may not be a ‘common’ auction, but the general auction is for one person to bid 4NT over their partner’s NT bid.
Tip: A 4NT bid after any NT bid, provided no fit has been established, is best used as quantitative (inviting slam, so 4NT can be passed if the other person has a minimum). If you want to ask for aces, you can always use 4 (after a NT bid) as Gerber to ask for aces, or you could find a way to force and establish a fit first before bidding 4NT (because once a fit is established, a 4NT bid that follows would no doubt be an ace ask).
Here’s one for the Minorwood advocates:
Is North’s 4 bid Minorwood (asking for aces/key cards), or is it simply a competitive bid? My advice? Don’t play Minorwood at all! (Unless you are in a serious partnership where you have complete set rules stating when Minorwood is on or off.)
Now this auction below probably wins as the auction where it causes the most accidents:
1 Penalties
As South, we open 1NT (whatever range that could be, say 15-17 for simplicity), West doubles for penalties, and our partner North bids 2. Is that natural to play (i.e. a weak hand with 5+ that wants to play in hearts), or is it a transfer to spades? Yes, this is the million dollar question. Particularly at vulnerable, you would want to know what it is! Discuss this with your partner – this auction isn’t uncommon at all. Other similar examples would be for North to bid 2 or even 2 – are these bids natural, or is it ‘system on’ where 2 is Stayman and 2 is a transfer?
Tip: If the Double is not penalties, then play system on (i.e. 2 is Stayman, 2/2 is transfers, etc.) but if the Double is penalties, then system is off and bids are just natural to play (since it is important to be able to bid 2 or 2 as natural).
With these above auctions discussed, they should certainly help your partnership have lesser misunderstandings (than you currently have), and hopefully lead to better (or more normal?) results!