Decision-makers frequently find themselves required to make judgments that seem to depend upon specialized scientific, mathematical, or technical knowledge. When this happens, they often turn to experts -individuals with formal training, experience, achievements, and peer recognition in the field in question. Experts, in turn, often appeal to those in positions of power to support their ongoing work, framing it as an investment in information that can guide future decisions. In this way, it might appear that experts and decision-makers have a symbiotic relationship. Decision-makers want or need expert advice, and experts stand to benefit from offering such advice.Today, indeed, the buying and selling of expertise is a highly organized enterprise. Decision-makers often solicit expert advice by turning to a specific expert or by publishing requests for proposals to the relevant community of experts. Bureaucratic agencies establish advisory committees of experts to help them make decisions. Not waiting to be asked, experts, for their part, often market their services directly to potential clients. Universities, think tanks, and consulting firms vie among themselves to secure some of the billions of dollars in grants and contracts offered by government agencies and private firms seeking expert advice, technical support, or the benefits of research and development. Experts working for universities frequently submit grant proposals to government agencies and private entities suggesting valuable research they might conduct in exchange for financial support. In the United States, for example, government agencies including the Department of Defense, the Department of Energy, and the National Institutes of Health, among others, support billions of dollars in scientific and technical research every year.The partnership between decision-makers and experts, however, is not always a happy one. In the political realm, at least, the history of this relationship often has been fraught with mistrust and hostility. Decision-makers have rejected the advice of experts since time immemorial. In the Hebrew bible, the Book of Kings relates the story of Rehoboam, successor to Solomon. Rehoboam rejected the counsel of his father's experienced advisors and followed his own judgment. The result was a rebellion and the secession of the northern segment of the Israelite kingdom. More recently, experts have sounded the alarm on innumerable crises of the modern era, but all too often are frustrated by the sclerotic response of the government. And, of course, experts themselves are hardly perfect. To cite a recent example, as America's