I examine the usefulness (relevance and timeliness) of earnings announcements in two emerging markets, the Johannesburg Stock Exchange (JSE) and the Bolsa Mexicana de Valores Stock Exchange (BMV). A weighted least-squares regression is used to test the association of book values of earnings and equity with firm market value. I find that, on JSE and BMV, earnings and/or book value of equity are value relevant in explaining stock prices. I also find that this association is greater in 2000 as compared to 1998 on the BMV. Regarding timeliness, I find that earnings announcements are accompanied by unusually different returns on JSE, but not on BMV. Market infrastructure, specifically insider-trading rules, may explain BMV results. I suggest that accounting and market infrastructure interact and that such interaction is valuable input to the Financial Accounting Standards Board (FASB) and International Accounting Standards Board (IASB) in their deliberations regarding one set of accounting regulations for all countries. © 2006 University of Illinois.