Just as an example: you've set up an observation point to watch for illegal dumpers and observe a truck 3 kilometers away illegally discharging hazardous waste. You use the laser range finder to determine where it is, and you radio to a patrol car to head to those coordinates before they get away. Without the range finder, you'd be guessing where they are and radioing things like, "they're about a hundred yards Northwest of that big oak tree," "you're almost there, just a couple more hillocks over," etc. It doesn't work very well. It's also handy in search-and-rescue operations, where you're trying to figure out where something you're seeing is so that you can direct the search.