This study explores whether the practice of Integrated Reporting (IR) in firm annual reporting improve managerial operational decision-making, in the context of generalist and specialist CEOs. Generalist CEOs have a broader set of managerial knowledge not specific to a particular firm or an industry while specialist CEOs possess narrower but deep firm-specific or industry-specific knowledge. Existing literature indicates that generalist CEOs exhibit higher agency issues due to greater job-hopping incentives and often exhibit poor firm performance due to their lack of firm-specific knowledge. This study proposes that high-quality IR practice can compensate for generalist CEOs’ dearth of firm-specific knowledge and mitigate their agency issues, thereby improving operational efficiency. On the other hand, specialist CEOs a priori possess firm-specific expertise and are expected to configure and align firm resources efficiently. IR quality is measured using proprietary data from PricewaterhouseCoopers (PwC) UK covering FTSE 350 firms’ corporate reporting quality. This study finds that generalist CEOs exhibit poor operational efficiency, and high-quality IR practice can improve their operational efficiency by compensating for their deficiency in firm-specific knowledge, relative to specialist CEOs. Additionally, generalist CEOs did not exhibit poor operational efficiency in the COVID-19 pandemic years (2020-2021) and that high-quality IR further aided their decision-making, resulting in greater firm operational efficiency, consistent with generalist CEOs superior performance in situations of crises, and this capacity is magnified in the presence of effective communication. Finally, the study identifies specific conditions under which IR practices are particularly effective for firms with generalist CEOs: (1) when the firm's board function is less effective, suggesting that high-quality SR can help mitigate agency issues associated with generalist CEOs by improving communication and transparency within the firm; and (2) when the firm is less complex, consistent with generalist CEOs’ a priori broad skill set and ability to manage increasingly complex organizations.