Heat a grill to medium high heat.
In a small bowl combine the butter, Parmesan cheese, oregano, parsley, garlic, salt, and pepper. Mix well.
Tear off two pieces of foil, about 18 inches long. Center the zucchini and squash in the middle of the foil.
Spread the butter mixture all over top of the zucchini and squash. Fold up the sides of the foil leaving an inch or two vent in the top.
Place the foil packet on the grill and cook for 15-20 minutes. Remove from grill and serve immediately.