Much of the unfinished business for the human race seems to consist of harms, threats, or risks of one kind or another, insufficiently controlled. The United Nations Millennium Declaration, adopted by the UN General Assembly in September 2000, lays out among its key objectives a daunting array of such harms to be controlled. The declaration lists, among others, hunger, war, genocide, weapons of mass destruction, international terrorism, the “world drug problem,” transnational crime, smuggling of human beings, money laundering, illicit traffic in small arms and light weapons, anti-personnel mines, extreme poverty, child mortality, HIV/Aids, malaria, other emerging infectious diseases, natural and man-made disasters, violence and discrimination against women, involvement of children in armed conflict, the sale of children, child prostitution, child pornography, and loss of the world's environmental resources. Many other major policy challenges can be naturally labeled and described in similar terms. Societies seek in turn to reduce violence and crime, pollution, fraud, occupational hazards, transportation hazards, corruption, many forms of discrimination, product-safety risks, and so on.

This book examines the distinctive operational challenges that the task of controlling harms entails, pressing the claim that anyone involved at any level in the control or mitigation of harms (of any type) might benefit from understanding the distinctive character of this task, and mastering some distinctive patterns of thought and action that go with it.

The idea that this subject is worth addressing at such a high level of generality may seem ridiculous to some, and for a variety of reasons.