Lamb shoulder comes from the upper front shoulder of the lamb. The shoulder of any animal bears a lot of weight and will be a tough cut that needs to be cooked low and slow in order to break down the connective tissue and make it tender. It is different from the "leg of lamb," which comes from the rear leg, and is leaner and more tender. The shoulder has a higher fat content, is richer in flavor and is less expensive than the lamb leg. Because of the higher fat content, it is also more forgiving and stays juicier.