This article examines the relation between investor sentiment and returns in private markets. Relative to more liquid public markets, private investment markets exhibit significant limits to arbitrage that restrict an investor's ability to counteract mispricing. Using vector autoregressive models, we find a positive and economically significant relation between investor sentiment and subsequent private market returns. We provide further long-horizon regression evidence suggesting that private commercial real estate markets are susceptible to prolonged periods of sentiment-induced mispricing as the inability to short-sell in periods of overvaluation and restricted access to credit in periods of undervaluation prevents arbitrageurs from entering the market.A growing behavioral approach in the economics and finance literature recognizes the bounded rationality and psychological biases of investors who often rely on and are influenced by computational shortcuts, heuristics, frame dependence and intuition when making decisions in a complicated and uncertain world with market frictions (e.g., Kahneman, Slovic and Tversky 1982, Barberis andThaler 2003). As a result, changes in asset prices may be driven by more than changes in market fundamentals. 1 Furthermore, these temporary price deviations can persist if there are significant limits to arbitrage as shown theoretically by De Long et al. (1990) and Shleifer and Vishny (1997), among others. Recent empirical research suggests this movement away from