In the first half-decade after the fall of the Berlin Wall, the UN Security Council repeatedly decreed mandatory economic sanctions programmes under Chapter VII of the UN Charter. Some of the programmes were severely criticized for their allegedly disproportionate effects on the populations of target states. The authors identify economic sanctions as a coerctve instrument and assess the applicability of international law standards, including the traditional criteria of necessity, proportionality and discrimination, to mandatory UN economic sanctions programmes. After an overview of the theory of economic sanctions and their place among strategic instruments of enforcement, the authors review the instances of mandatory UN economic sanctions programmes, assessing their effects on the populations of the target states and the extent of the Council's consideration of international legal norms in designing and carrying out sanctions. Concluding that the Council has given inadequate consideration to international law standards in implementing these programmes, the authors propose five legal principles for mandatory economic sanctions programmes: that highly coercive sanctions follow prescribed contingencies; that they be necessary and proportionate; that the sanctioners reasonably maximize discrimination between combatants and noncombatants; that sanctions programmes be periodically assessed; and that relief be provided to injured third parties.