Sprinkle the brisket on both sides with salt and pepper. Combine the Worcestershire sauce and water in a mister.
Prepare a fire for indirect-heat cooking in your smoker (the coals on one side only) with a water pan. Use oak wood chips, chunks or logs and keep up a good level of smoke. The smoker is ready when the temperature is between 275 and 300. If you have a pellet smoker then use oak pellets, water pan and set temperature to 250.
Put the brisket in the smoker on the cool side of the grate and close the lid. Cook for 6 hours, adding wood as needed to keep the fire burning evenly. At this point, test the brisket with an instant-read thermometer; the internal temperature should read 165.
Remove the brisket from the smoker. Spray it with some of the Worcestershire solution (there will be a lot leftover), wrap it in butcher paper and return it to the smoker. Let it cook in the paper for 2 hours longer.
Remove the wrapped brisket from the smoker and place it in an empty cooler or a 200 degree oven for 3 or 4 hours. The brisket is done when a toothpick passes effortlessly through the fat or an instant-read thermometer inserted into the center registers at least 185 but preferably as high as 203.