Nearly all sub-genres of whiskey abide by a strict set of regulations, and Irish whiskey is no exception. First and foremost, it must be distilled and matured in Ireland – well, duh. Secondly, it must come from a mash of malted cereals with or without whole grains of other cereals, which has been fermented by the action of yeast, distilled at an ABV of no more than 94.8 per cent, and aged for at least three years in wooden casks. The resulting spirit must have a minimum ABV of 40 per cent.