N-S are vulnerable.  You are South.

You hold:        ♠ K4

                        ♥ AKQ5

                        ♦ AQJ

                        ♣ KJT4

Your left-hand opponent (West) opens 1♠, and Partner bids 3♣, showing long Clubs and a weak hand.  At this vulnerability it is safe to assume that Partner has seven Clubs, all the more so considering that you have three of the Club honors in your own hand.  Even though West is almost certain to hold the ♠A and the ♦K, slam looks possible.  Do you bid 6♣ or 6NT?  The answer is 6NT, protecting your ♠K from the opening lead.  It’s called “right-siding the contract” and here is the complete deal:

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