which kernel patches should I apply while compiling Debian kernels?

["H. S." <greatexcalibur@yahoo.com>]

This may sound like a dumb question but should one apply debian kernel 
patches to a Debian source kernel before compiling one? e.g. I am right 
now working on kernel source of 2.6.9. Are the patches included in this 
source or should I select and install the ones listed by:
$> COLUMNS=160 dpkg -l kernel-patch*

specially the ones which are kernel-patch-<string>?

And how is kernel-patch-debian-2.6.9 related to kernel-source-2.6.9?

thanks,
->HS