The intensification of the environmental crisis has led stakeholders to pay increasing attention to corporate environmental transparency (CET). One obvious manifestation of this interest is that they require companies to present openness and disclose various information related to the environment. As an influential stakeholder group, policy-makers have also attached greater significance to the adoption of environmental policies based on information disclosure. For example, the International Sustainability Standards Board (ISSB), whose objective is to develop global sustainability disclosure standards, was established at the 2021 United Nations Climate Change Conference (COP26). In policy-making practice, transparency is often advocated as a prerequisite for legitimacy, policy efficiency, and good governance. The direction of accounting research is often inextricably linked to changes in the field of practice. In recent years, the concept of transparency has attracted extensive attention among accounting scholars. However, current research tends to use corporate environmental disclosure as a measure of corporate transparency. In the context of the general absence of environmental disclosure regulation, and therefore of standardised (and comparable) disclosures, this trend is highly controversial. Some scholars have critically commented that in addition to corporate environmental disclosure, there are other channels, such as government websites, media news reports, etc., through which to make corporate environmental information transparent to the public. As the country with the world’s highest share of carbon emissions, China is determined to accelerate various reform measures to achieve the carbon neutrality it has committed to reaching by 2060. Since 2017, China has implemented a mandatory environmental disclosure policy to promote the environmental transparency of listed companies and in so doing provides a promising policy environment and comparable standards for conducting CET research. Therefore, as a response to the academic call for more studies on the complex concept of transparency in the environmental accounting field, this thesis focuses particularly on the concept of CET and its related practices in the Chinese context. The objective of this thesis is to develop a measure of CET and to apply that measure to assess both the environmental transparency of listed companies in China and the impact environmental transparency has on corporate financial performance. Furthermore, the thesis also aims to gain an in-depth understanding of the internal and external driving forces behind CET. To achieve this goal, the thesis set five specific research objectives and asked five research questions. Meeting these objectives and answering these questions involved both finding empirical results (such as correlations) and searching for explanations to gain a deeper understanding of causal mechanisms. Driven by its research objectives and questions, this thesis follows a pragmatism philosophical stance. This paradigm can reconcile the contradiction between research objectives which stems from the long-standing subjective and objective debate between positivism and constructivism. In addition, pragmatism is regarded as providing philosophical and theoretical elements of mixed methods research design that lend mixed research argumentative coherence and validity. Therefore, a mixed research design is chosen for this thesis because the application of both quantitative and qualitative research methods contributes to a more comprehensive and in-depth understanding of the subject (i.e., CET) of the thesis. Guided by the mixed methods research design, this thesis consists of quantitative and qualitative investigations. There are two main findings in the quantitative investigation. First, the environmental transparency of Chinese listed companies does not meet the expectations of policy-makers. This finding is based on the assessment of CET in the Chinese context. Specifically, the mandatory environmental disclosure policy is not well followed; listed companies are suspected of concealing information about significant environmental administrative penalties, and there is a strong sense of mistrust among stakeholder groups towards corporate environmental disclosure, etc. Second, a significant negative correlation between CET and corporate financial performance was obtained through regression analysis on the sample companies. That finding shows that in the short term greater environmental transparency means higher environmental resource allocation, which in turn affects resource inputs in the production process and consequently has a negative impact on profits. In addition, the qualitative investigation identifies the internal and external driving factors behind CET in the Chinese context. First, the internal driving forces are accountability and impression management. The interviewees suggest that, while society’s awareness of corporate environmental accountability is the starting point of CET-related practices, an underlying motivation for these practices is impression management. It is worth mentioning that whether or not the board of directors is an internal driving force behind CET is still controversial. Second, the external driving forces are regulation and stakeholder pressure. The interviewees generally agree that it is the government and its regulatory policies that have an overwhelming influence on CET in the Chinese context. In addition, stakeholder groups, such as investors, the public, third parties, and industrial competitors, are thought to exert varying degrees of pressure to have CET in China. The findings of this thesis have rich theoretical and practical implications. In terms of theoretical implications, this thesis not only supports and develops legitimacy and signalling theories in the environmental disclosure field, but also expands the application scope of stakeholder theory. In addition, the thesis indicates that government intervention theory may have strong explanatory power in the Chinese context. In terms of practical implications, several recommendations are made to environmental policy-makers. For example, legal requirements for mandatory environmental disclosure should be considered; environmental disclosure items need to be improved; reward and penalty mechanisms need to be established; environmental assurance standards need to be developed; and, green financial policies need to be optimised. The findings of this thesis also contribute to existing knowledge. First, the thesis contributes new evidence to the argument that corporate environmental disclosure does not fully represent transparency. Second, the thesis establishes a conceptual framework for CET and contributes a measure of CET and so responds to the calls for more work that reviews existing research on transparency and which explores its measure and significance. Third, the thesis extends the existing studies on CET in emerging economies. Finally, the empirical finding in this thesis expands the previous literature on the relationship between CET and corporate financial performance, thus making an important contribution to knowledge. This thesis sheds light on future research potential. In light of the exploratory nature of its qualitative investigation, there are still several unknown issues that require further academic attention, such as how much explanatory power the impression management perspective has on the CET, whether and to what extent the board of directors influences CET, and, how exactly peer pressure affects CET, etc. In addition, another promising direction would be to explore what consequences CET can have for companies over a long period of time, as the green transformation often takes a relatively long time to achieve. Future research on the long-term impact of CET will help to understand the true mechanisms of CET’s effect on companies.