This study investigates stock market anomalies in the Kuala Lumpur Stock Exchange (KLSE), Malaysia, with some comparisons with three other Far-Eastern markets, namely the Stock Exchange of Singapore (SES), the Stock Exchange of Thailand (SET) and the Stock Exchange of Hong Kong (SEHK). The main anomaly investigated is overreaction in the KLSE. Seasonality and firm size effects, which are usually associated with the overreaction effect, are also examined individually, and in the context of the overreaction effect. The impact of time-varying risk on overreaction is also investigated. First, stock market seasonality across four markets - KLSE, SES, SET and SEHK- is examined. The evidence suggests the existence of December and January effects in Singapore and Hong Kong respectively. A Chinese New Year effect is observed in all countries except Thailand. Next, stock market overreaction in the KLSE is investigated. Two portfolios of extreme stocks (based on their past 3-year excess returns) are formed, and their performance is measured in the next three years for evidence of overreaction. The initial results are consistent with overreaction; winner (loser) portfolios, which outperform (underperform) the market in the prior period, underperform (outperform) the market in the next period. The reversal in performance is more dramatic for losers. Further analyses show that risk and size factors cannot explain fully the observed phenomenon. A seasonal pattern is revealed in the excess returns of winners and losers; there is a pronounced February effect in both. Moreover, the February effect is observed to be greater for smaller firms. Lastly, a post-script chapter is included whereby the effect of the recent Asian economic turmoil on the markets, and on KLSE overreaction, is looked at. It is found that several months into the crisis, both winners and losers underperform the market.