Crosstalk fixes are changes to wires and drivers, each with a cost and a side effect. A cost-effective set of fixes is the right answer, not a guaranteed minimal one: greedy ordering by benefit per cost can overshoot, and every fix has to be verified because it changes windows, delays and other nets' coupling. This topic orders the fixes by benefit per cost, shows what spacing and shielding deliver, compares changing the victim with changing the aggressor, and gives a verification routine.