In this paper, we examine and compare the form of the flow-performance relationship for U.S. retail and institutional mutual funds. We provide evidence that the convex form of the flow-performance function documented by previous research characterizes mostly the relationship in the upper region of the performance scale. In contrast, the flow-performance relationship for the low-performance region appears to be concave. Furthermore, we document that the observed convexity is more pronounced for retail funds, while the concavity can be mainly attributed to institutional funds.