The first essay, “The Cross-Section of Idiosyncratic Volatility and Expected Returns in Currency Markets” studies the effect of idiosyncratic volatility (IV OL) in currency markets. In equity markets, Ang et al. (2006) and Ang et al. (2009) show that stocks with higher IVOL have lower returns. This negative relation between IV OL and returns is called the “idiosyncratic volatility puzzle.” We study whether the same IV OL puzzle exists in currency markets. We measure IV OL based on the model proposed by Verdelhan (2018). We use daily data for 33 major currencies ranged from July 2006 to March 2021. We find that the IVOL puzzle also exists in currency markets, especially for developing markets currencies. We also analyze the sources of IVOL f...