Using a large sample of earnings press releases by Australian firms, we compare multiple attributes of non-GAAP earnings measures with their closest GAAP equivalent. We find that, on average, non-GAAP earnings are more persistent, smoother, more value relevant, and have higher predictive power than their closest GAAP equivalent. However, the same set of non-GAAP earnings disclosures are also less conservative and less timely than their closest GAAP equivalent. The results are consistent with non-GAAP earnings measures reflecting a reversal of the trade-off between the valuation and stewardship roles of accounting inherent in accounting standards and the way they are applied. We also find that differences in several of these attributes between GAAP and non-GAAP earnings are more evident in larger firms, firms with lower market-to-book ratios, firms with a higher proportion of independent directors, and firms that report profits rather than losses. Our evidence is consistent with the argument that accounting standards impose significant amounts of conditional conservatism at some cost to the valuation role of accounting information. Non-GAAP earnings measures can therefore be seen as a response to the challenges faced by a single GAAP performance measure in satisfying the competing demands of value relevance and stewardship.