 Climate “contrarians” challenge key conclusions of “mainstream” climate science, such as those of the IPCC, in a host of public venues: blogs, newspaper op-ed pieces, television and radio interviews, Congressional hearings and, occasionally, scientific journals. Those considered contrarians come in many varieties, from climate scientists who consider headline attribution claims to be insufficiently justified—they are usually described as climate “skeptics”—to individuals and groups from outside of climate science whose primary motivation is to block climate policy, in some cases by “manufacturing doubt” about the reality or seriousness of anthropogenic climate change; they are commonly labelled climate “deniers” (see, e.g., Oreskes &amp; Conway 2010; Ranalli 2012). (The use of these labels varies, however.) Contrarians have played a role in creating or sustaining a number of public controversies related to climate science. Four of these are discussed very briefly below, along with some recent philosophical work reflecting on the impact of contrarian dissent.