How would you go about fixing rust on a vehicle's body work?

[XJ Jeep]

How would you go about fixing rust on a vehicle's body work?

 

[Northernexplorer]

Cut the rusty panels off and weld some new ones in. Do not do dodgy work like body filler on the body work as rust will show up again

 

[Dirt lover]

cut the rust out and replace it with new panels mate. If it is not too bad sand it down put rust converter on it some body filler and paint over it