Combine chicken and taco seasoning mix in a skillet over medium high heat. Add the amount of water directed on package for taco filling. Bring to a boil. Reduce heat to medium. Simmer 5-10 minutes, stirring occasionally, or until water is evaporated. Stir in corn and cook until thoroughly heated. Meanwhile, heat taco shells or tortillas as directed on package. Fill each shell with 1/4 cup chicken filling. Top each with lettuce, tomato, olives and cheese.