Try to do no harm on opening lead. Computer simulations are showing that when it comes to opening leads we should follow the Hippocratic Oath and try to ‘Do no harm.” It turns out that the biggest part of opening leads is too avoid giving up a trick rather than always trying to actively work on cashing or setting up tricks. Against NT we lead 4th from our longest and strongest because we are willing to give up a trick to get a head start in setting up our suit. However, in suit contracts, we are only going to get a trick or two in a side suit before declarer or dummy runs out of them. As a result, we cannot afford to give up any of our possible tricks. So, against suits we lead so as not to give away a trick. In general, the less you lead from, the better.