The purpose of this article is to provoke discussion on the priorities of research in mathematics education. Mathematics education is a vast field, and there is always a possibility that no one direction stands out in its importance. Each researcher has some list of priorities and "pet topics." The author ventures to propose a research program that could be the most fruitful in research direction. The ideas presented in this article have been developed while meditating on the nature of the core of mathematics education, as presented by Wittmann (1995), who advocated seeing mathematics education as a "design science."