Mark N. Fox is the Chairman of the Mandan, Hidatsa, and Arikara Nation. Fox is a veteran of the U.S. Marine Corps and earned his law degree in 1993 from the University of North Dakota. First elected Chairman in 2014, Fox is currently serving his second term.

Chairman Fox currently serves on three federal advisory boards for the Department of Energy, Department of Interior, and the Environmental Protection Agency. He previously served on advisory boards with the Internal Revenue Service and the National Indian Gaming Commission as well. Chairman Fox also served on various national and tribal boards, including the Intertribal Monitoring Association on Trust Funds (ITMA) and four terms as Treasurer of the National Indian Gaming Association (NIGA).

Chairman Fox has also been the Vice Chairman of the United Tribes Technical Center and the United Tribes of North Dakota. He was recently elected Chairman of the Coalition of Large Tribes (COLT). 

A fierce proponent of tribal sovereignty, Chairman Fox has dedicated his administration to improving the lives of all MHA Nation members. Under his leadership, tribal members have received increased education, addiction, and health services. Chairman Fox has also expanded and enhanced tribal infrastructure and transparency in governmental affairs. 

Chairman Fox is renowned for his work in the areas of taxation, gaming, energy, and economic development. In his personal time, Chairman Fox enjoys participating in events that endorse good health and endurance challenges.