In a large bowl, combine the zucchini, yellow squash, bell peppers, red onion and corn. Drizzle with the olive oil and season with the salt and pepper.
Toss to combine and then transfer the vegetables to the grill.
Cook for 8 to 10 minutes, or until the vegetables are tender and lightly charred.
Transfer the grilled vegetables back to the bowl and toss with your favorite vinaigrette.