When it gets easy to maintain a down/stay without distractions, it's a good idea to add some.

Harper could handle the pepperoni a short distance away, so now we make it a little more challenging...

Even more...

Ultimate challenge!

Now, three dogs and one pepperoni.

A pepperoni slice each. Don't worry - each dog got a pepperoni treat after all this work!

Piper is not amused!