This thesis revisits the valuation relevance of a firm’s carbon risk profile using a broader notion of a firm’s carbon risk profile, which includes carbon risk exposure, and carbon risk mitigation. Prior studies that have begun to explore the value relevance of a firm’s carbon risk profile, focus on carbon risk exposure, typically proxied using its historic carbon emissions, documenting a valuation penalty on high carbon emitters due to the perceived presence of economically significant off-balance sheet liabilities. However, from extant literature, a firm’s carbon risk profile can be conceptualised into two broad aspects, namely carbon risk exposure and carbon risk mitigation. Therefore, the reliance on emissions is limited, not only due to the historic nature of this measure but, because it only partially captures a firm’s carbon risk exposure that is conceptualised in extant literature, and because it ignores how firms respond to carbon risks.This thesis is undertaken in two stages. Initially, I develop measures that capture a broader notion of a firm’s carbon risk profile. I use extant literature and interviews with 28 managers of high carbon emitting firms and five ESG analysts to develop three specific measures that include ‘other carbon risk exposure’, aside from tonnage of emissions typically found in extant literature, ‘emissions reductions’ and ‘proactive carbon responses’ (PCRs), identified from publicly available data. Next, I test the valuation effects of the broader notion of a firm’s carbon risk profile using a modified Ohlson valuation model and a sample of 51 ASX200 firms (122 firm-year observations) reporting under the National Greenhouse and Energy Reporting scheme with the necessary financial and market data. The study documents that, on average, a one standard deviation difference in the level of ‘other carbon-risk exposure’ results in a penalty of 11% of market capitalisation of the sample firms on average. This penalty is in addition to the penalty found to exist on high emitters of 10% of market capitalisation for the sample firms on average. I also find that PCRs partially mitigate the documented penalty on high emitters. The interview results suggest that in terms of PCRs, managers and analysts perceive value in firms developing intangible carbon-related capabilities around adaptability, carbon leadership and stakeholder trust. The empirical results are consistent with this proposition since I find that adaptability, carbon leadership and stakeholder trust partially mitigate the emissions penalty. Taken together these results are consistent with the argument that capital markets impound the valuation impacts of other carbon-risk exposure, aside from emissions, and PCRs identified from publicly available information in firm valuations. Furthermore, I find no evidence that emissions reductions are able to mitigate the penalty assigned to high emitters. These findings are consistent with industry concerns that emissions represent an historic measure that is not perceived to be informative in assessing the future carbon risk profile of a firm. This study contributes to literature through the development of measures of a broader carbon risk profile that are future oriented, based on publicly available information, thereby moving away from the reliance on historic emissions. Further, this study has captured some of the additional future carbon risk incremental to that captured in historic emissions and, provides empirical evidence to suggest that a firm’s broader carbon risk profile is value relevant. These findings progress the discussion on the disclosure of carbon-related non-financial information that is of interest to capital markets, which can inform corporates regarding carbon risk mitigation and policy setters in their future policy deliberations.