Cut aluminum foil into four (4) square sheets approximately 12" x 12". Set aside.
In a large mixing boil, add the potatoes, shrimp, sausage, corn, onions, garlic, olive oil, Old Bay Seasoning, salt, and pepper. Use tongs to toss together until all of the ingredients are evenly coated with the oil and seasonings.
Evenly divide the mixture between the four prepared foil packets, then seal by folding in two sides to meet in the middle and then folding in the opposite sides until well sealed.
Place foil packets onto the main grill rack, close the grill cover, and cook for 12 to 16 minutes. Check at 12 minutes and if the shrimp is cooked, transfer the shrimp onto a plate, re-seal the packets, and grill the remaining ingredients for another 3 to 4 minutes until the potatoes are fork-tender. Serve immediately.
Notes
Storage tips: while this dish is best served the day of, you can store leftovers in an airtight container in the refrigerator for up to 3 to 4 days. You can also freeze leftovers in a freezer-safe container for up to one month; thaw in the refrigerator overnight before reheating.