|Alma mater||University of California Davis|
|Known for||Co-owner of Niʻihau|
|Relatives||Aubrey Robinson (grandfather)|
Robinson was born c. 1941 to Lester Beauclerk Robinson (1901–69) and Helen Matthew Robinson (1910–2002).  He attended the University of California Davis, graduating with a degree in agronomy and ranch management. After college, he served in the US Army before returning to Hawaii, where he initially worked at the Koolau Ranch on Kauaʻi seven years and then operated a commercial fishing vessel on Kauaʻi for another seven years.
Robinson and his brother Bruce own[ verification needed] the approximately 70-square-mile (180 km2) island of Niʻihau in the Hawaiian island chain, which has been in the private possession of their family since their great-great-grandmother Elizabeth McHutchinson Sinclair (1800–92) purchased it from King Kamehameha V for US$10,000 in gold. He is also the manager of a private botanical garden on the Hawaiian island of Kauaʻi.  Robinson makes his home on Kauaʻi, but visits Niʻihau at least once per week on average.
I've spent eighteen years and more than $250,000 doing this work, and I estimate it would cost the government or environmental groups $10–20 million to create a comparable reserve. I've done all phases of it myself; scouting, seed collecting, seed germination, planting, transplanting, watering, growing, fencing, fertilizing, and insecticide spraying. In most environmental groups or botanical gardens, the work is highly compartmentalized. You get your plant scouts, your seed collectors, your nurserymen, and people on the grounds. They all have different duties, and their duties never change, so none of them has a broad overview of what's going on. They don't know what specific problems there are at various stages where you're trying to produce the plants. 
Robinson has repeatedly expressed his desire to keep Niʻihau privately owned so as to preserve the environment and traditions of its 150 to 200 native Hawaiian inhabitants, and has occasionally taken large financial losses to do so. As under their predecessors, the Robinsons have kept Niʻihau largely closed to outside visitors, though a few hunters and other tourists are admitted each year—but with limited or no contact with the islanders. The Robinsons continue to ban radios, televisions and mobile phones on the island, in an effort to preserve as much of the indigenous island culture as possible. In 1997, Robinson estimated that between $8–9 million was spent to keep people employed, not counting the free housing and free meat provided to the 150–200 Niʻihau islanders.  After 135 years of operation, the ranch on the island shut down in 1999, rendering all its inhabitants unemployed. 
Robinson expressed concerns about his family's ability to continue to maintain their ownership of Niʻihau, due to pressure from the federal and state governments and environmental groups. Taxes on the island have taken much of the profits from the Robinsons' interests in agricultural companies.  Keith Robinson has compared his plight on Niʻihau to Ruby Ridge and the Waco Siege, threatening to defend his island with force if necessary.[ citation needed]
In 2005 a documentary on him was released titled Robinson Crusader.
Sinclair-Robinson family tree
- Anthony Sommer (May 14, 1999). "The Robinson family and native Hawaiians are turning to the military and tourism for income". Honolulu Star-Bulletin. Retrieved October 25, 2010.
- Keith Robinson (July 26, 1997). "Niihau:Other Views". Honolulu Star-Bulletin. Archived from the original on July 8, 2011. Retrieved October 25, 2010.
- Eric P. Olsen (February 18, 2003). "Hawaii Plantsman Confounds Greenies; Keith Robinson has a green thumb with endangered plants and a belief that the 'green' tactics used by the environmental establishment are a total waste of time". Inisght on the News blog. CBS Interactive Business Network. Retrieved August 23, 2012.
- Margaret A. Haapoja (August 22, 2005). "Hawaii's rare breeds: after decades of solitary effort to save Hawaii's rarest plants, one man halts his efforts in response to government-environmentalist attacks private property rights". The New American. Retrieved December 6, 2010.
- Moore, Trish. “Robinson Family may sell Niihau, Leave Hawaii.” Honolulu Star-Bulletin 17 April 1998: N/A. Web.