The Heartland Institute is an American conservative and libertarian 501(c)(3) nonprofit public policy think tank headquartered in Chicago, Illinois, founded in 1984 by investor David H. Padden and Joseph L. Bast. It promotes free-market policies, education reform, and limited government intervention in social and economic issues. The institute is widely known for its climate change skepticism, actively rejecting the scientific consensus on climate change through publications, conferences, advocacy, and alternative reports like the Non-intergovernmental Panel on Climate Change (NIPCC) series since the 2000s, positioning itself as a counter to mainstream environmental policies. Historically, the institute collaborated with tobacco company Philip Morris in the 1990s to discredit health risks of secondhand smoke and lobby against smoking bans. Leaked documents in 2012 revealed funding sources including the Charles G. Koch Foundation and anonymous donors, as well as strategic goals to undermine climate science education. The institute receives grants from entities like the Donors Capital Fund (DCF) and has been criticized by scientists and environmental groups for disinformation campaigns on climate and tobacco. Despite controversies, it remains active in policy debates, authoring works such as 'Climatism' and 'Unstoppable Solar Cycles' to advance its free-market ideology.