Possible to supply 2 shields off the 5V on board supply??

Hi,
just asking is it safe to pull 5V for 2 different shields from an arduino board? or will i need a seperate 5V power supply for one of them? I am also using the 3.3V supply for another one

Who knows? You don't say what these shields are and more importantly what current they draw. Given these details we stand a fighting chance.