waterproofing before tiling in shower

Hi,

Not sure wheher right forum.
Am about to re-do bathroom and install a showerbath. Have been told by some that i should make sure walls are waterproof under tiles (where shower goes), not just bang on tiles/grout - and some other said don't bother.

Part of the wall will be re-built with plasterboard, part will be old tiles remove (from plaster board) and re tile whole bathroom

Experiences either way? what should i do

I've not got much experience, but I found reference on here to a product called aquapanel from Wickes which can be used as an alternative to plasterboard and is designed to be a backing for shower walls etc.

Our dividing wall between toilet and bathroom is coming down as I type and then a door will be closed up using the aquapanel before I tile for the shower enclosure.... fingers crossed it all goes well

Aqupanel is the real deal on this one, however, green plasterboard is adequate if your tilings good.