Twenty-five years after it was launched, China's "One Child" population control policy is credited with cutting population growth to an all time low and contributing to two decades of spectacular economic development. But the costs associated with the policy are also apparent and are rising: a growing proportion of elderly with inadequate government or family support, a disproportionately high number of male births attributable to sex selective abortion, increased female infant and child mortality rates, and the collapse of a credible government birth reporting system. Today, as China contemplates the future of the policy, many argue that a change that allows couples to have two children will not lead to uncontrollable population growth. Instead, it could help meet the fertility desires of most Chinese couples; avoid a worsening of the demographic and social consequences already evident; and relieve the Chinese government of the immense financial and political costs of enforcing an unpopular policy. But changes will need to come soon if China is to avert even greater negative consequences of the policy.