Chapter One estimates financial statement comparability measures of accounting disclosures surrounding the enactment and implementation of SFAS No. 131 to examine potential variation in comparability associated with the segment reporting regime shift. Initial results indicate an increase in comparability levels for firms reporting reformulated segments in the post-SFAS No. 131 period. However, greater decreases in financial statement comparability are associated with firms that experienced increases in the number of segments disclosed due to application of the revised standard. Overall, results suggest that segment information reformulated according to how companies manage their businesses enhances financial comparability, but greater segment information disaggregation attributed to SFAS No. 131 adoption diminishes comparability. Chapter Two examines whether financial statement comparability enhances the usefulness of information to capital markets participants. I use three measures of financial statement comparability to investigate the role of comparability in the stock price sensitivity to firm-specific earnings news. I find that information content of earnings is greater for firms with higher comparability, suggesting that comparability contributes to information usefulness for investors in equity valuation decisions. I offer further support that comparability enhances usefulness through increased response to positive earnings surprises. This influence is pronounced for the earnings news of small firms, high volatility firms, growth/value firms, and firms with low return on assets, indicating that comparability is more informative for more speculative stocks. Overall, financial statement comparability appears to enhance the usefulness of information to capital market participants by increasing the informativeness of firm-specific earnings news.