This paper expands on the existing literature on information asymmetry by testing if herding exists. We test herd behavior in a transparent and order-driven market using intraday data. We propose (1) a modification in the herding measure, (2) that investors tend to herd more based on fundamental analysis relative to technical analysis, and (3) that informational asymmetry can be identified by applying the informational cascade model to herding. In general, our analyses agree with the existing literature that herding tends to be more prevalent with small stocks and in economic downturns and that investors are more likely to herd when selling rather than buying stocks. Most importantly, our results reveal the existence of informational cascades, which highlights the crucial role played by so-called fashion leaders, especially when more informed investors trade with "noise". © 2009 Elsevier B.V. All rights reserved.