Cullen Center is a skyscraper complex in Downtown Houston, Texas, United States. The complex is now managed by Brookfield Properties. Previously Trizec Properties owned all four office buildings. The complex includes the headquarters of the Houston Fire Department and KBR, and it formerly included the headquarters of Continental Airlines. The buildings include 1600 Smith (formerly Continental Center I), 600 Jefferson (formerly Continental Center II), KBR Tower, and 500 Jefferson Street.