The entire island is owned by the Robinson family who purchased it from the Kingdom of Hawaii for $10,000. It was said that the purchaser, Elizabeth Sinclair (later Sinclair-Robinson), bought the island in preference to other real estate parcels such as Waikīkī, Pearl Harbor and the island of Lana'i. There is a small US Navy installation at which a handful of naval personnel are stationed.
The island has a few hundred permanent inhabitants nearly all of whom are native Hawaiians. They support themselves largely by subsistence farming and many are employees of the ranch owned by the Robinsons. The native Hawaiians lead a rural, low-tech life. They speak the Hawaiian language and keep traditions alive. This is enabled by terms in the purchase contract obligating the owner to help preserve Hawaiian culture and tradition. Ni'ihau is the only one of the Hawaiian islands on which the Hawaiian language is the main form of communications.
Ni'ihau is also known as the "Forbidden Island". This is due to the fact that until recently, the island was off-limits to all but family members, US Navy personnel, government officials and expressly invited guests. Now, tourists can go on one of a limited number of supervised tours or hunting safaris.
On the beaches of the island are found shells which are the only shells to be classified as gems. Ni'ihau shells and the jewelry made from them are very popular. Many, especially those with darker and richer color, are collectors items. The sale of shells and shell jewelry provide an additional source of income for the local populace.