Prepare the grill and heat the coals.
Soak bamboo skewers in water.
Toss shrimp with 1 T. olive oil, to coat.
Cut potatoes into similar sized chunks and toss in the remaining oil and 1 t. cajun seasoning.
De-string the corn, but leave the husks intact. You can brush with butter or oil here, if you would like.
Melt butter and add in 1 t. cajun seasoning and salt.
Fold the husks back up over the corn and place on the grill. Turn every 5 minutes.
Skewer potatoes and place on the grill.
Skewer shrimp and place on the grill. Cook for 3-4 minutes on each side.
Brush cooked shrimp with the butter and seasoning mixture. Remove from grill.
Remove potatoes when they are soft all the way through.
Remove corn after 15-20 minutes. Brush the corn with the remaining seasoning and butter mixture.