Scepticism that human activities are altering the global climate in seriously damaging ways is widely regarded as an aberrant position and a deliberately manufactured phenomenon. The charge against sceptics is that they try to undermine the credibility of mainstream climate science in a ploy to delay progressive climate policies, and thus protect the vested interests of fossil fuel stakeholders. Sceptics are also considered beholden to political conservatism and conservative lobbies, which fear that the climate change agenda is being set by socialist and Green interests and that climate policies would undermine the neo-liberal capitalist status quo. Many observers blame elite sceptics for persistent public scepticism on the climate issue. This study tests these constructions of climate change scepticism through a grounded investigation of the underlying worldview assumptions of sceptics, their conceptual repertoires, and the thematic focal points of their rhetoric. A sample of sceptic texts from Australian sceptics is qualitatively investigated, as well as subjected to computerised textual analysis with a view to identifying characteristic concepts and themes. The study reports (Chapter 4) that climate change scepticism occupies a broad conceptual space which is best understood when distinctions are made between core and concomitant classes of scepticism, subordinate centres of scepticism, and various lower order objects of scepticism. It proposes taxonomies to capture the variety of beliefs and intensities of belief amongst sceptics. It advocates the adoption of semantically accurate and neutral labels for different sceptic persuasions. Next, the underlying worldview assumptions of sceptics are described (Chapter 5) and associated with the cultural archetypes posited by grid-group Cultural Theory. It finds evidence that sceptics are rooted in the individualist worldview, that some are leaning towards the hierarchist view, and that all sceptics stand antithetical to the egalitarian view. This is followed by a grounded computer assisted analysis of the key concepts and themes in the text sample (Chapter 6). Consistent with the evidence of an individualist/hierarchist cultural rationality amongst sceptics, the grounded analysis reveals that sceptics support climate responses that privilege neo-liberal capitalism. However, it also reveals a strong concern for sound science and good governance, and that many sceptics consider the style of the scientific debate and climate related political decision-making a major stumbling block, over and above their epistemic challenges of the physical science. The study next (Chapter 7) zooms in on the climate policy views of sceptics, again through a computer assisted textual analysis, and finds evidence of two distinct approaches, a puritan approach that insists on consistency between the perceived lack of conclusive physical evidence about the causes and impacts of climate change and climate policy, as opposed to a pragmatist approach that acknowledges the inevitability of a carbon constrained future but wishes to direct climate policy towards a more nationalistic, careful and measured response pattern. The policy views of seven high profile sceptics, each from a different professional background, are analysed in depth (Chapter 8) in order to corroborate the evidence presented by the computer assisted analysis. It finds that many sceptics are ideologically close to an innovation response to the climate problem, which emphasises energy security and technological solutions to the climate problem. Sceptics are found to be opposed to a green response, which proposes interventionist macro-economic policies aimed at restructuring the prevailing economic systems. The study concludes (Chapter 9) that the sceptic phenomenon is much more heterogeneous than generally understood or acknowledged, and that much of the sceptic rationale rest on relatively neutral notions of due process and responsible governance. It argues that observers need to be mindful of the finer nuances in sceptic thought, how to differentiate between entrenched sceptics and the doubtful and agnostic ones, and how to frame science and policy communications so that they resonate with sceptics’ unique set of worldviews and assumptions.