Scholars and policymakers want to know how much investment is sufficient to attain high-performing schools. Examining education spending in a highly regarded education system can yield insights for the United States. This paper explores conceptualizations and applications of adequacy in the United States and the Republic of Korea. Our exploratory study rests on the premise that adequacy, and the level of investment it implies, is a localized concept. This discussion highlights the fact that context matters because any query on whether a system has sufficient spending begs the question, "Sufficient for what?" In the Republic of Korea, policymakers consider the question in the context of adequate delivery of its national curriculum. In the United States, that question is answered in the context of adequate student achievement. It is important to acknowledge these different perspectives because Korean and U.S. policymakers thus face different negotiables on the appropriate way to spend public educational dollars.