Book excerpt: The explosion of scientific information is exacerbating the information gap between richer/poorer, educated/less-educated publics. The proliferation of media technology and the popularity of the Internet help some keep up with these developments but also make it more likely others fall further behind. This is taking place in a globalizing economy and society that further complicates the division between information haves and have-nots and compounds the challenge of communicating about emerging science and technology to increasingly diverse audiences. Journalism about science and technology must fill this gap, yet journalists and journalism students themselves struggle to keep abreast of contemporary scientific developments. Scientist - aided by public relations and public information professionals - must get their stories out, not only to other scientists but also to broader public audiences. Funding agencies increasingly expect their grantees to engage in outreach and education, and such activity can be seen as both a survival strategy and an ethical imperative for taxpayer-supported, university-based research. Science communication, often in new forms, must expand to meet all these needs. Providing a comprehensive introduction to students, professionals and scholars in this area is a unique challenge because practitioners in these fields must grasp both the principles of science and the principles of science communication while understanding the social contexts of each. For this reason, science journalism and science communication are often addressed only in advanced undergraduate or graduate specialty courses rather than covered exhaustively in lower-division courses. Even so, those entering the field rarely will have a comprehensive background in both science and communication studies. This circumstance underscores the importance of compiling useful reference materials. The Encyclopedia of Science and Technology Communication presents resources and strategies for science communicators, including theoretical material and background on recent controversies and key institutional actors and sources. Science communicators need to understand more than how to interpret scientific facts and conclusions; they need to understand basic elements of the politics, sociology, and philosophy of science, as well as relevant media and communication theory, principles of risk communication, new trends, and how to evaluate the effectiveness of science communication programmes, to mention just a few of the major challenges. This work will help to develop and enhance such understanding as it addresses these challenges and more. Topics covered include: advocacy, policy, and research organizations environmental and health communication philosophy of science media theory and science communication informal science education science journalism as a profession risk communication theory public understanding of science pseudo-science in the news special problems in reporting science and technology science communication ethics.