Twenty-four hours a day – seven days a week – 365 days a year, the more than 2,000 people of the Architect of the Capitol (AOC) serve the nation as proud stewards of some of the most iconic buildings and grounds in the world. Across the U.S. Capitol campus, architects, engineers and technicians design, enhance, and maintain new and historic structures, spaces, and building systems. Employees in various trades such as electricians, plumbers, masons, and carpenters maintain the facilities and infrastructure in optimal condition. Gardeners and grounds keepers create colorful displays and care for hundreds of acres of lawns and plantings. All of these efforts are directed at making the work of the Congress, the Supreme Court and Library of Congress – and the experience of the millions of visitors annually – as smooth, efficient and enjoyable as possible. Guides and Visitor Assistants at the U.S. Capitol Visitor Center provide an exceptional experience for visitors to the nation's Capitol.