From the days corporate social responsibility (CSR) became a topic of discussion, extensive amount of research is conducted on CSR in Western countries but still there is relatively little focus on some developed and developing countries. Moreover, relatively little research has compared cross-country and cross-sector CSR variations. Starting from this point, this article investigates the extent of CSR variations of a highly developed (the United States), a developed (South Korea) and a developing country (Turkey) through a detailed comparative analysis of CSR information disclosure on corporate websites of 50 CSR active companies listed in stock exchange markets of each country. For cross-sector comparison, these target corporations are selected from five different industries including consumer electronics & telecommunication services, automobile & component manufacturers, food & beverages, retail stores, and major banks. The research opens the door for more in-depth empirical study on why there are cross-country and cross-sector variations in CSR.