Dr. Riley E. Dunlap of Oklahoma State University will discuss. Global warming had become widely recognized as a problem by the early 1990s, but a long-term and ever-evolving campaign to deny its reality and significance has turned contemporary climate change into a major controversy. The basic findings of climate science are constantly challenged by a growing set of interconnected actors who portray climate change as uncertain, even a hoax, leading significant segments of the public and numerous policy-makers to dismiss its importance and thus the need to take action to reduce carbon emissions. Key actors in what has been termed the denial counter-movement, the economic and ideological interests motivating them, and the primary strategies and tactics they employ will be outlined, with emphasis on how they have all evolved over the past quarter century. Finally, a brief assessment of the wide-ranging impacts of climate change denial, including the obstruction of USA and international policy-making, will be given.