Abstract: The transportation of water across nanochannels has received extensive attention due to potential applications in water treatment and because of its similarities with biological water channels such as aquaporins. This article reviews some recent progress in the understanding of water transportation across nanochannels. We will focus on the on-off gating behavior in response to external mechanical and electrical signals and noise, enhancement by structure outside the channel, and uni-directional transportation driven by charges close to a channel or electric field.