Lomborg was inspired by an interview with economist Julian Lincoln Simon to undertake an assessment of publicly available data, and published his findings as a series of articles in Politiken.

These formed the basis of the book, in which Lomborg argues against a range of what he considers overly pessimistic claims about environmental issues and their impact on human prosperity.

Lomborg argues that environmentalists' concerns over pollution, environmental degradation, decline in natural resources, and climate change are overstated, and outlines his opposition to policy responses like the Kyoto Protocol, deeming them insufficient and causing more harm than good based on cost–benefit analysis.

The book generally received negative reviews from the scientific community,[1] focusing on the author's methodology, data issues, theories and concepts.

[1] The Danish Ecological Council, an advisory committee on environmental issues, published a "counter-publication" which criticised Lomborg's methods and approach in his book.

[1] I would fail one of my undergraduate students if they were to write such trash The Union of Concerned Scientists published a critique of the book, highlighting reviews by Peter Gleick, Jerry D. Mahlman, Thomas Lovejoy, Norman Myers, Jeffrey Harvey, E. O. Wilson and Stuart Pimm.

They concluded that the book fits squarely in a tradition of contrarian environmental works, which may gain temporary prominence but ultimately fail to stand up to scientific scrutiny.

[9] Harvey compared the book unfavourably to University undergraduate quality, and added "ecology is the most complex of sciences and Lomborg has never done a shred of work in the field".

"[1] In January 2002, a heading from Scientific American read, "Misleading Math about the Earth" and contained set of essays written by scientists on the book.

"[16] David Pimentel wrote a critical review in Population and Environment, particularly taking issue with Lomborg's argument on soil erosion, pesticides, deforestation and water resources.

A separate article examining the book's overall approach by Kathryn Schulz took issue with the framing of Lomborg's conclusions, asking "[why] does he weigh the environment only against hospitals and childcare, rather than against, say, industry subsidies and defense spending?".

It stated that "This is one of the most valuable books on public policy—not merely environmental policy—to have been written for the intelligent general reader in the past ten years...The Skeptical Environmentalist is a triumph.

"[23] In August 2001, The Guardian published three exclusive essays by Lomborg and hosted an online debate with him, describing him as "Europe's most controversial environmental thinker".

"[26] Rolling Stone wrote that "Lomborg pulls off the remarkable feat of welding the techno-optimism of the Internet age with a lefty's concern for the fate of the planet.

"[6]Chris Lavers gave a mixed review in The Guardian, saying Lomborg "is clearly committed to rubbishing the views of hand-picked environmentalists, frequently the very silly ones such as Ehrlich, whom professionals have been ignoring for decades" and criticising his framing of deforestation.

[30] One critical article, "The Skeptical Environmentalist: A Case Study in the Manufacture of News", attributes the book's media success to its initial, influential supporters, who linked its message to a European visit from United States president George W.

Articles pegging the claims of The Skeptical Environmentalist to Bush's European visit ran later that week in the U.K's The Express and Daily Telegraph, and Canada's Toronto Star.

[2] Richard C. Bell, writing for Worldwatch argued that many reviews in prominent publications were written by individuals with prior association with Lomborg, "instead of seeking scientists with a critical perspective."

In The Wall Street Journal, a review was published by the Competitive Enterprise Institute's Ronald Bailey, someone "who had earlier written a book called The True State of the World, from which much of Lomborg's claims were taken."

"[31] On 5 September 2001, at a promotional event at a Borders book shop in Oxford, England, British environmentalist author Mark Lynas threw a cream pie in Lomborg's face.

Several environmental scientists brought a total of three complaints against Lomborg to the Danish Committees on Scientific Dishonesty (DCSD), a body under Denmark's Ministry of Science, Technology and Innovation.

Lomborg was asked whether he regarded the book as a "debate" publication, and thereby not under the purview of the DCSD, or as a scientific work; he chose the latter, clearing the way for the inquiry that followed.

A six-month review took place and on 6 January 2003, a 17-page DCSD ruling was released, in which the Committees decided that The Skeptical Environmentalist showed "systematic one-sidedness" and was scientifically dishonest, but Lomborg was innocent of wrongdoing due to a lack of expertise in the relevant fields.

He also argued the report could jeopardise his employment at the Danish Institute for Environmental Assessment and some of his critics attempted to do this, although government officials denied his posting would be impacted.

[41][40] The ruling was also debated in parliament, and science minister Helge Sander asked the Danish Research Agency to establish a working group to scrutinise the DCSD's procedures.

[36][38] Jim Giles wrote a 2003 retrospective on the book in Nature, saying it was "packed with facts and figures, yet it was the emotional response that it inspired that will be best remembered," and argued that it would have little long-lasting influence.

They concluded that "the book is anyway sure to go down in history as an unreliable source of information and argumentation, being one of the most severely criticized texts issued ever by a prestigious academic publisher".