This deal is from the Portland Pairs in 2010, with a small alteration.  You open the South hand three hearts and partner raises you to six hearts.
West leads a diamond and you wonder whether partner should have tried harder for a grand slam.
However, after winning the ace of diamonds you cash the heart ace and East discards a diamond.
You are pleased not to be in seven hearts now, but how do you proceed?


Solution

You will have to be lucky now; your best chance is to find West with a specific distribution (4513 or 3523) along with the spade queen and play to reduce your trumps to the same length as West's.
Cash the top clubs throwing a diamond and ruff a club in hand.  Take the spade king and finesse the spade jack, cash the spade ace throwing a diamond.  Then ruff a spade or diamond back to hand depending on West's spade length.
Both West and South are now down to four trumps each, simply exit with a low trump and West is forced to lead up to your KQ10 of hearts.