Leads are notoriously difficult. When we have a three card honor sequence against notrump, it's almost always right to lead it (and we lead the top card). Against suit contracts, we only need two cards in a sequence to lead the top card. Those leads usually help set up tricks for our side and normally don't give away too much. Unfortunately, they can be helpful for a declarer who is paying close attention. 

We've all fallen victim to this combination. 

We choose to lead the K from KQx against a suit contract. We are distraught to see dummy's Jxx with declarer winning the ace. Oops. That certainly can happen. Usually, though, a lead like the J from J109x is a great, safe play. With good declarers, nothing is safe. Let's see if we can be a good declarer on this deal. 

Vul:None Dlr: S	K87  A63  876  KQ82
65  K94  Q104  J10973		J1094  Q872  KJ52  4
	AQ32  J105  A93  A65