Dealings within corporate networks are common in Japan and can pose a significant risk to investors. Evidence suggests that such practices may have a negative impact on shareholder value. This study sheds light on the issue by examining some cases of inter-corporate and related-party transactions. The study also gives an account of the historical development of corporate structures in Japan, reviews ongoing efforts to improve corporate governance in Japan, and explores relevant disclosure issues. Protection of minority shareholders can be enhanced by improving the frequency and content of disclosures, requiring shareholder approval for major transactions, and reducing the number of parent/subsidiary listings.