Balance (also referred to as the Principle of Balance) refers to the dual obligation of governments to establish a system of control to prevent abuse, trafficking, and diversion of narcotic drugs while, at the same time, ensuring their medical availability. Although opioid analgesics are controlled drugs, they also are essential drugs and are indispensable for the relief of pain. Opioids, including those in the therapeutic group of morphine, should be accessible to all patients who need them for relief of pain. Governments must take steps to ensure the adequate availability of opioids for medical and scientific purposes.