The dissertation consists of two essays. The first essay investigates how oil market factors impact on liquidity commonality in global equity markets. I identify two transmitting channels of the effect on liquidity commonality, namely oil price return and volatility. Using a sample of firms drawn from 50 countries spanning from Jan 1995 to Dec 2015, I find that both effects in oil explain the liquidity commonality in countries with higher integration to oil market. In addition, I show that oil volatility effect is more pronounced in net oil exporters compared to net oil importers after controlling for oil sensitivity. My findings suggest that oil volatility effect on liquidity commonality is more substantial for high oil sensitive countries than oil price return effect except five OPEC members, where liquidity commonality is highly influenced by oil the return along with volatility. These results are robust to controlling for possible sources of liquidity commonality as found in the literature. In the second essay, I study the impact of stock liquidity on firms’ future investments. Since stock liquidity decreases the cost of equity, I expect firms’ future investments to increase with stock liquidity. Secondly, I argue that this relation is more pronounced in more financially constrained firms because of their limited access to external capital. Using a sample of more than 9800 firms, from 21 emerging markets and spanning from 2000 to 2015, I find supportive and robust evidence of a positive association between stock liquidity and firms’ future investments. Furthermore, my findings strongly suggest that the liquidity impact on corporate investments is highly influenced by the firms’ financial constraint levels, using four different definitions of financial constraints. My findings are robust due to controlling for other determinants of future investment suggested in the previous literature, and due to controlling for the country and time effects. In addition, the results seem to be consistent with the use of alternative measures of corporate investments and stock liquidity and with alternative model specifications and estimation methodologies.