In recent years evidence has accumulated that nearby spiral galaxies 
are surrounded by massive haloes of neutral and ionised gas. These 
gaseous haloes have low angular momentum with respect to their disc 
and also show inflow motion. They are clearly analogous to the High 
Velocity Clouds observed around the Milky Way.
A fraction of this halo gas is certainly produced by supernova 
outflows from the disc (galactic fountains) but in addition there is 
also evidence for a substantial accretion of material from the 
Intergalactic Medium (IGM). This implies that nearby spiral galaxies 
are currently acquiring gas from the IGM and thus they are still 
growing today.
After reviewing recent observational results I will present a 
dynamical model for the formation of gaseous haloes that takes into 
account both galactic fountains and gas accretion.