The Marianas' top activity among Americans is scuba diving and snorkeling. In additional to the coral reefs you might expect, the waters around the islands were the scene of fierce fighting during World War II and there are many ship wrecks and even rusting tanks stuck on the seabed.
Many Asian particularly South Koreans visitors come to the CNMI for gambling especially on Tinian, and karaoke/hostess bars. Saipan has a thriving but illegal prostitution industry, most of the workers being from China or the Philippines.
As a US territory, Americans and American Samoan citizens can come here and work with no special visa or requirements, and they can stay and work indefinitely. Foreigners must go through the rigorous process of obtaining a US work permit. Citizens of most other nations need a permit from the Department of Labor. Most businesses prefer to employ Filipinos, and also citizens of Thailand, China, South Korea and Bangladesh. See the United States work section for more information.
Because of its autonomous status, labor laws in the commonwealth exist outside US Federal laws. As a result the minimum wage is currently, $5.05 per hour. Protection of employees is weaker than anywhere else in the US. The Northern Mariana Islands have been accused by the US Federal Government and various other organizations for enslaving foreign workers particularly from China and the Philippines and immigrants in sweatshops and prostitution.