1. Cook orzo according to package directions, omitting salt and fat. Drain. Place orzo in a medium bowl. Stir in parsley and 1/4 teaspoon salt; cover and keep warm.
2. While orzo cooks, melt 1 tablespoon butter in a large nonstick skillet over medium-high heat. Sprinkle shrimp with remaining 1/4 teaspoon salt. Add half of shrimp to pan; sauté 2 minutes or until almost done. Transfer shrimp to a plate. Melt 1 teaspoon butter in pan. Add remaining shrimp to pan; sauté 2 minutes or until almost done. Transfer to plate.
3. Melt remaining 1 tablespoon butter in pan. Add garlic to pan; cook 30 seconds, stirring constantly. Stir in shrimp, juice, and pepper; cook 1 minute or until shrimp are done.