Malaysian corporations have to disclose corporate social responsibility, and a typical genre for disclosure is CSR reports. These reports incorporate other discourses which indicate the presence of interdiscursivity. The article examines interdiscursivity in Malaysian CSR reports. It selects the CSR reports of 10 major corporations and pursues an interdiscursive analysis which involves four sequential stages. CSR reports contain discourses of public relations, sustainability, strategic management, compliance and financial accounting. Although the discourses are often multisemiotic, language maintains primacy in content, while (...) image tends to exemplify or simplify content. These discourses constitute an interdiscursive profile, and it has central and auxiliary discourses. The central discourse is public relations discourse, and it promotes corporations helping and not harming society. The auxiliary discourses are sustainability, strategic management, compliance and financial accounting discourses, and these discourses mitigate the promotional focus. Interdiscursivity enables the primarily promotional CSR reports to not seem overtly promotional. The choice of discourses is probably influenced by coercive, mimetic and normative reasons. These discourses enhance the reliability of CSR reports because their disclosure is anchored to various CSR aspects, international or reporting practices and professional domains. Interdiscursivity helps to build stakeholders’ confidence in disclosure and, therefore, in corporations. It joins other functions in CSR reports to convey corporations as agents of positive social change. The article also probes the relationship between interdiscursivity and intertextuality and advances a matrix of intertextual–interdiscursive use. (shrink)