U.S.-China science and technology (S&T) relations are shaped by two paradoxes. First, as many have noted, global problems require global solutions, but while the science that drives these solutions is increasingly collaborative spanning different disciplines, institutions, and geographical locations, it is also an essential component of national power. The results of scientific discovery are public goods, but they can also lead to first-mover advantages and the ability to lock others out of important markets. As a result, China and the United States are collaborators as well as competitors for talent, new ideas, market share, and status and prestige.