Technical innovation is ubiquitous in contemporary society and contributes to its extraordinarily dynamic character. Sometimes these innovations have significant effects on the state of the environment or on human health and they have stimulated efforts to develop second order technologies to ameliorate those effects. The development of the automobile and its impact on life in the United States and throughout the world is an example. The story of modern environmental regulation more generally includes chapters filled with examples of similar efforts to respond to an enormous array of technological advances.