Throughout the late 19th and early 20th century, the Museum was involved in groundbreaking projects of exploration that included expeditions to the North Pole, Siberia, Mongolia, Gobi, and the Congo. During this time, new sections of the Museum were also opened, including the African Mammals Hall and the Hall of Ocean Life. New halls would continue to open throughout the 20th century, making the Museum one of the most important research and public learning centers in the world.
In the 1990s and 2000s, the Museum continued to grow, as it still does today, adding new attractions for visitors and researchers. New facilities for the Museum's research library were opened in 1992, a Zeiss Star Projector was built in 1999, and the Museum started hosting overnight stays for families with its A Night at the Museum program in 2006. By adding new exhibits and activities, along with continued projects of exploration, the American Museum of Natural History continues to push deeper into the realm of knowledge, providing a service to society that will not be forgotten.