This book discusses the ways in which science, the touchstone of reliable knowledge in modern society, changed dramatically in the second half of the 20th century, becoming less trustworthy through excessive competitiveness and conflicts of interest. Fraud became common enough that organized efforts to combat it now include a federal Office of Research Integrity. Competent minority opinions are sometimes suppressed so that policy makers, media and the public are presented with biased or incomplete information. Evidence tending to challenge established theories is sometimes rejected. While most would agree in the abstract that science can go wrong, few would consider-despite interesting contrary evidence-that official consensus about the origins of the universe or the causes of global warming might be mistaken.