Professor Sonu Heyjung of the KMU International Business School (KIBS) at Kookmin University received the Accounting Journal Outstanding Paper Award at the 2026 Summer International Conference and Joint Academic Conference of the Korean Accounting Association. The *Accounting Journal* Outstanding Paper Award is presented to one paper published in the previous year’s *Accounting Journal*—a KCI Q1-rated academic journal published by the Korean Accounting Association—that demonstrates outstanding research achievements.

The award-winning paper is titled “The Impact of Mergers Among Small and Medium-Sized Accounting Firms in 2019 on the Audit Market,” authored by Professor Sonu Heyjung (first author) and Professor Lee KwangJin of Soongsil University (corresponding author). Based on cases of mergers among small and medium-sized accounting firms that occurred in Korea in 2019, this paper empirically analyzed the impact of such mergers on the audit market, including audit fees, audit hours, and market share. The results showed that audit fees and audit hours increased across the audit market following the mergers; this is interpreted as being driven more by changes in the accounting system—such as the implementation of the New External Audit Act—rather than by the mergers themselves. Conversely, the market share of the merging firms increased significantly, demonstrating that mergers among small and medium-sized accounting firms can have a certain impact on their competitiveness and standing in the audit market.

Professor Sonu stated, “This study aimed to provide insights for discussions on accounting audit policies and regulations by empirically analyzing the impact of mergers among small and medium-sized accounting firms on the audit market,” adding, “I plan to continue my research on changes in accounting systems and the audit market.”