In short, you can do anything you would do in any other situation.
   For instance, if you are doing lap or other siding, bring it down to where you want it to terminate, and apply a waterproof coat that extends up under the bottom of the siding.

   But do the "parge coat" first, it will save you time and your back over doing it after siding is up. Take that parging down until it overlaps your waterproof barrier a few inches.

   If it's deco rock or brick, simply take your scratch coat down to your waterproofing, again with a few inches of overlap.

   And if you do stucco, well you get the point. The key is overlap, creating a continuous path for water to the drain or earth and not into your home.

Jesse
ICF Pro Builders / Norco Construction
Southern Oregon